Mask assembly

ABSTRACT

A nasal assembly for delivering breathable gas to a patient includes a frame having an integrally formed first connector portion. A nozzle assembly includes a gusset or base portion and a pair of nozzles. At least one inlet conduit is structured to deliver breathable gas into the frame and nozzle assembly for breathing by the patient. A pair of second connector portions are removably and rotatably connected to respective first connector portions of the frame and are in communication with respective inlet conduits, e.g., directly or via angle connectors. A headgear assembly is removably connected to the pair of second connector portions and/or the angle connectors so as to maintain the frame and the nozzle assembly in a desired adjusted position on the patient&#39;s face.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/587,824, filed Sep. 30, 2019, which is a continuation of U.S. patentapplication Ser. No. 16/003,341, filed Jun. 8, 2018, now pending, whichis a continuation of U.S. patent application Ser. No. 15/493,741, filedApr. 21, 2017, now abandoned, which is a continuation of U.S. patentapplication Ser. No. 14/988,890, filed Jan. 6, 2016, now U.S. Pat. No.11,090,455, which is a continuation of U.S. patent application Ser. No.11/962,621, filed Dec. 21, 2007, now abandoned, which is a continuationof U.S. patent application Ser. No. 10/781,929, filed Feb. 20, 2004, nowU.S. Pat. No. 7,318,437, which claims the benefit of U.S. ProvisionalApplication Nos. 60/529,696, filed Dec. 16, 2003, 60/494,119, filed Aug.12, 2003, 60/448,465, filed Feb. 21, 2003, 60/482,872, filed Jun. 27,2003, and 60/488,810, filed Jul. 22, 2003, each of which is incorporatedherein in its entirety.

FIELD OF THE INVENTION

The present invention relates to a nasal assembly used for treatment,e.g., of Sleep Disordered Breathing (SDB) with Continuous PositiveAirway Pressure (CPAP) or Non-invasive Positive Pressure Ventilation(NPPV).

BACKGROUND OF THE INVENTION

Some nasal assemblies used in the treatment of SDB are designed forinsertion into the nasal passages of the patient. Air or otherbreathable gas is supplied by a blower and passed along a flexibleconduit to the nasal assembly.

The nasal assembly generally includes a relatively rigid shell, e.g., aframe, and a pair of nozzles (which may be in the form of nasal pillows,nasal prongs, cannula, or nasal puffs) that are mounted on the rigidshell and structured to be inserted into the nasal passages of thepatient. The nozzles are usually held in place using a headgearassembly, the relatively rigid shell and headgear assembly being joinedusing some form of connector.

One form of known nasal assembly is described in U.S. Pat. No. 4,782,832(Trimble et al.). Trimble discloses a nasal puff assembly 20 thatincludes a nasal puff 22 adapted to be worn adjacent the nose of apatient, together with a harness assembly 24 adapted to be worn over thehead of the patient. The harness assembly 24 is designed to operativelyhold puff 22 adjacent and partially within the nasal passages of thepatient.

The puff 22 is in the form of a generally Y-shaped rigid hollow plenumchamber 28 together with a pair of laterally spaced apart nares elements30. Adjustability of the nares elements 30 may be provided by rotatablymounting the elements 30 to the plenum chamber 28 and mounting theelements 30 in slots permitting selective lateral positioning of theelements 30 with respect to each other. Also, the harness assembly 24may be adjusted to adjust the fit and seal of the nares elements 30during use. That is, the force required to maintain a sufficient seal isdirectly associated with the force required to maintain a desired fit.Thus, adjustment of the fit or stability of the nasal assembly directlyaffects the seal, which can adversely affect patient comfort.

Other examples of nasal pillows or cannula mounted to rigid shells aredisclosed in U.S. Pat. Nos. 5,724,965 and 6,431,172.

A nasal mask assembly manufactured by Viasys, i.e., Spiritus, includes aplenum chamber with a pair of adjacent or laterally spaced nareselements. A harness assembly is engaged with the plenum chamber toadjust the fit and seal of the nares elements during use. Similar toTrimble, adjustment of the fit or stability of the nasal assemblydirectly affects the seal, which can adversely affect patient comfort.

A nasal mask assembly manufactured by InnoMed, i.e., Nasal Aire,includes a plenum chamber with a pair of adjacent or laterally spacednares elements. The nares elements are structured to engage within themucosal surfaces or internal passages of the patient's nose to maintainthe nasal mask assembly on the patient's face and to provide a seal.See, e.g., U.S. Pat. No. 5,533,506.

A nasal mask assembly manufactured by Stevenson Industries (see U.S.Pat. No. 6,012,455), i.e., CPAP-Pro, includes a dental anchor, aplatform, and air supply tubes having nasal pads, wherein the platformsupports the air supply tubes. The dental anchor is sized to be engagedbetween the teeth in the patient's mouth so as to retain the assembly inplace.

PCT Application Publication No. WO 00/13751 discloses a device thatincludes gas delivery elements positioned into engagement with thepatient's nose by a mouthpiece fitted to the patient's teeth.

A common problem with known nasal assemblies, such as those discussedabove, is patient comfort. For example, the prongs tend to irritate thepatient's nose due to the tension applied by the headgear assembly thatpulls the rigid shell and prongs towards the patient's nose.

Another problem is achievement of a sealing fit with the patient's nasalpassages without sacrificing patient comfort.

Another problem is irritation of the inside of the patient's nostrilscaused by contact with the prongs, e.g., an edge thereof.

Another problem is irritation of the inside of the patient's nostrilscaused by air jetting (air flow irritation) from the prongs.

Another problem is adjustment of the nasal assemblies relative to thenose and/or head of the patient so as to accommodate various shapes andangles of patient's noses.

Still another problem is the direct association between sealing andstability forces that can affect patient comfort.

SUMMARY OF THE INVENTION

One aspect of the invention is directed towards a nasal assembly thatprovides more comfort to the patient.

Another aspect of the invention is directed towards a nasal assemblythat provides an effective seal with the patient's nasal passages.Preferably, the nasal assembly is a nozzle assembly including nozzleswhich comfortably come into contact with the external rim of the naresand avoid the sensitive internal passages (e.g., mucosal surfaces orinternal passages) of the nasal passage.

Still another aspect of the invention is directed towards a nasalassembly that does not rely on tension from the headgear assembly toprovide an effective seal between the nozzles and the patient's nasalpassages.

Still another aspect of the invention is directed towards a nasalassembly that is unobtrusive.

Still another aspect of the invention is directed towards a nasalassembly that is easy to use.

Still another aspect of the invention is directed towards a nasalassembly that maintains a headgear adjustment setting.

Still another aspect of the invention is directed towards a nasalassembly that helps decouple sealing and stability forces. Specifically,one aspect of the invention is directed towards a nasal assembly that isstructured such that the stability forces that act to maintain the nasalassembly on the patient's face are separated or at least betterdistinguished from the sealing forces that act to maintain a sealbetween the nasal assembly and the patient's face.

Yet another aspect of the invention is directed towards a nasal assemblythat provides a greater range of movement for nozzles of the nasalassembly.

Another aspect of the invention provides a nasal assembly for deliveringbreathable gas to a patient. The nasal assembly includes a frame havinga main body and a side frame member provided on each lateral side of themain body, each side frame member including an integrally formed firstconnector portion. A nozzle assembly includes a gusset or base portionand a pair of nozzles. The nozzle assembly is coupled with the main bodyof the frame with the pair of nozzles structured to sealingly engagewith nasal passages of a patient's nose in use. A pair of inlet conduitsare structured to deliver breathable gas into the frame and nozzleassembly for breathing by the patient. A pair of second connectorportions are removably and rotatably connected to respective firstconnector portions of the frame. The second connector portions are incommunication with the inlet conduits via angle connectors. A headgearassembly is removably connected to at least one of the second connectorportions and the angle connectors so as to maintain the frame and thenozzle assembly in a desired adjusted position on the patient's face.

Other aspects, features and advantages of this invention will becomeapparent from the following detailed description when taken inconjunction with the accompanying drawings, which are a part of thisdisclosure and which illustrate, by way of example, principles of thisinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings facilitate an understanding of the variousembodiments of this invention. In such drawings:

FIG. 1 is a perspective view illustrating a partial nasal assemblyconstructed in accordance with an embodiment of the invention mounted toa patient's head and engaged with nasal passages of the patient;

FIG. 2 is a front view of a frame of the nasal assembly shown in FIG. 1with some parts removed for clarity;

FIG. 3 is a cross-sectional view of the frame shown in FIG. 2 ;

FIG. 4 is a side view of the frame shown in FIG. 2 ;

FIG. 5 is a front view of a nozzle assembly of the nasal assembly shownin FIG. 1 ;

FIG. 6 is a front cross-sectional view of the nozzle assembly shown inFIG. 5 ;

FIG. 7 is a side view of the nozzle assembly shown in FIG. 5 ;

FIG. 8 is a side cross-sectional view of the nozzle assembly shown inFIG. 5 ;

FIG. 9 is a perspective view of an embodiment of an inlet conduit andheadgear connector assembly of the nasal assembly shown in FIG. 1 ;

FIG. 10 is a rear perspective view of the inlet conduit and headgearconnector assembly shown in FIG. 9 ;

FIG. 11 is a perspective view of another embodiment of an inlet conduitand headgear connector assembly adapted to be used with the nasalassembly shown in FIG. 1 ;

FIG. 12 is a rear perspective view of the inlet conduit and headgearconnector assembly shown in FIG. 11 ;

FIG. 13 is a side view illustrating an over-the-head inlet conduitrouting for the nasal assembly shown in FIG. 1 ;

FIG. 14 is a side view illustrating an under-the-chin inlet conduitrouting for the nasal assembly shown in FIG. 1 ;

FIG. 15 is a perspective view illustrating a connector for use inrouting the inlet conduits over the head of the patient;

FIG. 16 is a perspective view illustrating a connector for use inrouting the inlet conduits under the chin of the patient;

FIG. 17 is a perspective view illustrating a flow generator connectorfor use in connecting the nasal assembly shown in FIG. 1 to apressurized supply;

FIG. 18 is a side view illustrating an embodiment of headgear componentsfor use with the nasal assembly shown in FIG. 1 ;

FIG. 19 is a schematic view illustrating a patient's nose having asubstantially flat alar angle;

FIG. 20 is a schematic view illustrating a patient's nose having asubstantially steep alar angle;

FIG. 21 is a schematic view illustrating an embodiment of a sealing zoneof a nozzle;

FIG. 22 is a graph illustrating average nostril ratios opening/entrance;

FIG. 23 is a schematic view illustrating an embodiment for calculating abase major axis of a nozzle;

FIG. 24 is a schematic view illustrating an embodiment for calculating abase minor axis of a nozzle;

FIG. 25 is a partial perspective view illustrating another embodiment ofa nasal assembly mounted to a patient's head and engaged with nasalpassages of the patient;

FIG. 26 is a partial front perspective view of the nasal assembly shownin FIG. 25 ;

FIG. 27 is a cross-sectional view of the nasal assembly shown in FIG. 25;

FIG. 28 is a front perspective view of a frame of the nasal assemblyshown in FIG. 25 ;

FIG. 29 is a rear perspective view of the frame shown in FIG. 28 ;

FIG. 30 is a partial front perspective view of a half of the nozzleassembly of the nasal assembly shown in FIG. 25 ;

FIG. 31 is a side cross-sectional view of the nozzle assembly shown inFIG. 30 ;

FIG. 32 is a perspective view illustrating an embodiment of an inletconduit and headgear connector assembly of the nasal assembly shown inFIG. 25 ;

FIG. 33 is a rear perspective view of the inlet conduit and headgearconnector assembly shown in FIG. 32 ;

FIG. 34 is a cross-sectional view of the inlet conduit and headgearconnector assembly shown in FIG. 32 with the flexible arms in phantom;

FIG. 35 is a perspective view of a flow generator connector for use inconnecting tubes for use with the nasal assembly shown in FIG. 25 to apressurized supply;

FIG. 36 is a side view illustrating the routing of the inlet conduits ofthe nasal assembly shown in FIG. 25 ;

FIG. 37 is a side view illustrating the nasal assembly shown in FIG. 25mounted to a patient's head;

FIG. 38 is a perspective view illustrating another embodiment of a nasalassembly mounted to a patient's head and engaged with nasal passages ofthe patient;

FIG. 38B is a perspective view illustrating an inlet conduit and aninlet conduit and headgear connector of the nasal assembly shown in FIG.38 ;

FIG. 39 is a perspective view of the nasal assembly shown in FIG. 38 ;

FIG. 40 is a perspective view of a frame of the nasal assembly shown inFIG. 38 ;

FIG. 41 is a perspective view of a nozzle assembly of the nasal assemblyshown in FIG. 38 ;

FIG. 42 is a perspective view illustrating the nozzle assembly shown inFIG. 41 mounted to the frame to shown in FIG. 40 ;

FIG. 43 is a cross-sectional view of the nasal assembly shown in FIG. 38;

FIG. 44 is a side cross-sectional view of the nasal assembly shown inFIG. 38 ;

FIG. 45 is a side view illustrating the nasal assembly shown in FIG. 38mounted to a patient's head showing two inlet configurations;

FIG. 46 is a schematic force diagram illustrating some of the forcesthat are developed when the nasal assembly shown in FIG. 38 is mountedto the patient's head;

FIG. 47 is a cross-sectional view of an embodiment of an inlet conduitengaged with an embodiment of an angle connector for deliveringbreathable gas;

FIG. 47B is a perspective view illustrating another embodiment of aninlet conduit;

FIG. 48 is a cross-sectional view illustrating another embodiment of aninlet conduit engaged with another embodiment of a flow generatorconnector for delivering breathable gas;

FIG. 48B is perspective view illustrating another embodiment of an inletconduit;

FIG. 49 is a perspective view illustrating an embodiment of an inletconduit of the nasal assembly shown in FIG. 38 ;

FIG. 50 is a side view illustrating the nasal assembly shown in FIG. 38prior to engagement with nasal passages of the patient;

FIG. 51 is a front view illustrating the nasal assembly shown in FIG. 38(in cross-section) engaged with nasal passages of the patient;

FIG. 52 is a perspective view illustrating another embodiment of a nasalassembly mounted to a patient's head and engaged with nasal passages ofthe patient with two inlet configurations shown;

FIG. 53 is a perspective view illustrating the nasal assembly shown inFIG. 52 ;

FIG. 54 is a cross-sectional view illustrating a nozzle assembly beingengaged with a frame of the nasal assembly shown in FIG. 52 ;

FIG. 55 is a perspective view illustrating an inlet conduit and headgearconnector assembly of the nasal assembly shown in FIG. 52 ;

FIG. 56 is a cross-sectional view illustrating the inlet conduit andheadgear connector assembly of the nasal assembly shown in FIG. 52 ;

FIG. 57 is a cross-sectional side view illustrating the nasal assemblyshown in FIG. 52 about to be engaged with nasal passages of the patient;

FIG. 58 is a front view illustrating the nasal assembly shown in FIG. 52(in cross-section) being engaged with nasal passages of the patient;

FIG. 59 is a perspective view illustrating another embodiment of a nasalassembly mounted to a patient's head and engaged with nasal passages ofthe patient;

FIG. 60 is a perspective view of the nasal assembly shown in FIG. 59removed from a patient's head;

FIG. 61 is an exploded view of a portion of the nasal assembly shown inFIG. 59 illustrating the frame, nozzle assembly, and clip thereof;

FIG. 62 is a perspective view of a portion of the nasal assembly shownin FIG. 59 illustrating the clip being engaged with the frame and nozzleassembly;

FIG. 63 is a perspective view of a portion of the nasal assembly shownin FIG. 59 illustrating the engagement between the frame, nozzleassembly, and clip;

FIG. 64 is a partial cross-sectional view of a portion of the nasalassembly shown in FIG. 59 illustrating the engagement between the frame,nozzle assembly, and clip;

FIG. 65 is a top perspective view of a portion of the nasal assemblyshown in FIG. 59 ;

FIG. 65A is a partial enlarged view of the cushion shown in FIG. 65 ;

FIG. 65B is a schematic diagram illustrating force distributionaccording to one aspect of the present invention;

FIG. 66 is a rear perspective view of a portion of an alternativeembodiment of a nasal assembly illustrating the engagement between theframe, nozzle assembly, and clip;

FIG. 67 is a rear perspective illustrating the engagement betweenanother embodiment of the frame, nozzle assembly, and clip;

FIG. 68 is a perspective view illustrating the nozzle assembly shown inFIG. 66 being engaged with the frame shown in FIG. 66 ;

FIG. 69 is a perspective view illustrating the nozzle assembly shown inFIG. 67 being engaged with the frame shown in FIG. 67 ;

FIG. 70 is a perspective view illustrating the clip shown in FIG. 66being engaged with the frame and nozzle assembly shown in FIG. 66 ;

FIG. 71 is a perspective view illustrating the clip shown in FIG. 67being engaged with the frame and nozzle assembly shown in FIG. 67 ;

FIG. 72 is a perspective view of a second connector portion of the nasalassembly shown in FIG. 59 ;

FIG. 73 is a cross-sectional view of a portion of the nasal assemblyshown in FIG. 59 illustrating the engagement between the frame, secondconnector portion, and angle connector;

FIG. 74 is a perspective view of an angle connector of the nasalassembly shown in FIG. 59 ;

FIG. 74B is a perspective similar to FIG. 74 but at a different angle;

FIG. 75 is a side view of the angle connector shown in FIG. 74 ;

FIG. 76 is a cross-sectional view of the angle connector shown in FIG.74 ;

FIG. 76A illustrates another embodiment of the present invention;

FIG. 76B is an exploded view of FIG. 76A;

FIG. 76C illustrates a second connector portion of the assembly of FIG.76A;

FIG. 76D illustrates an angle connector used in the assembly of FIG.76A;

FIG. 77 is a perspective view of a flow generator connector of the nasalassembly shown in FIG. 59 ;

FIG. 78 is a cross-sectional view of the flow generator connector shownin FIG. 77 ;

FIG. 79 is a cross-sectional view of an embodiment of an inlet conduitof the nasal assembly shown in FIG. 59 ;

FIG. 80 is a perspective view of headgear yoke of the headgear assemblyof the nasal assembly shown in FIG. 59 ;

FIG. 81 is a perspective view illustrating engagement between theheadgear yoke (FIG. 80 ) and angle connector (FIG. 74 );

FIG. 82 is a cross-section through line 82-82 of FIG. 81 ;

FIG. 83 is a perspective view of a headgear buckle of the nasal assemblyshown in FIG. 59 ;

FIG. 84 is a perspective view of the nasal assembly shown in FIG. 59illustrating the routing of the headgear assembly;

FIG. 85 is another perspective view of the nasal assembly shown in FIG.59 illustrating the routing of the headgear assembly;

FIG. 86 is a top view illustrating a nasal assembly constructed inaccordance with an embodiment of the invention;

FIG. 87 is a side view of the nasal assembly shown in FIG. 86 ;

FIG. 88 is a bottom view of the nasal assembly shown in FIG. 86 ;

FIG. 89 is an exploded view of a portion of the nasal assembly shown inFIG. 86 ;

FIG. 90 is a perspective view of a portion of an embodiment of a nasalassembly;

FIG. 91 is a top view of a headgear connector according to analternative embodiment of the invention;

FIG. 92 is a perspective view of an upper portion of a central conduitof the nasal assembly shown in FIG. 90 ;

FIG. 93 is a top view of the upper portion of the central conduit shownin FIG. 92 ;

FIG. 94 is a perspective view of a lower portion of a central conduit ofthe nasal assembly shown in FIG. 90 ;

FIG. 95 is a bottom view of the lower portion of the central conduitshown in FIG. 94 ;

FIG. 96 is a perspective view of an inlet conduit of the nasal assemblyshown in FIG. 86 ;

FIG. 96A is a schematic view of a Y-shaped inlet connector of the nasalassembly shown in FIG. 86 ;

FIG. 97 is a perspective view of an inlet connector of the nasalassembly shown in FIG. 86 ;

FIG. 97A is a schematic view of the nasal assembly shown in FIG. 86 withthe nozzles in a first position adjacent to the nasal passages of thepatient;

FIG. 97B is a schematic view of the nasal assembly shown in FIG. 86 withthe nozzles in a second position in sealing engagement with the nasalpassages of the patient;

FIG. 98 is a perspective view of another embodiment of a nasal assembly;

FIG. 99 is an enlarged perspective view of nozzles and a gusset portionof the nasal assembly shown in FIG. 98 ;

FIG. 100 is an enlarged perspective view of inlet conduits of the nasalassembly shown in FIG. 98 ;

FIG. 101 is a front perspective view illustrating the nasal assemblyshown in FIG. 98 mounted to a patient's head;

FIG. 102 is a rear perspective view illustrating the nasal assemblyshown in FIG. 98 mounted to a patient's head;

FIG. 103 is a front perspective view illustrating the nasal assemblyshown in FIG. 98 engaged with nasal passages of the patient;

FIG. 104 is a side perspective view illustrating the nasal assemblyshown in FIG. 98 engaged with the nasal passages of the patient;

FIG. 105 is a side view illustrating the nasal assembly shown in FIG. 98engaged with the nasal passages of the patient;

FIG. 106 is a front perspective view illustrating the nasal assemblyshown in FIG. 98 engaged with nasal passages of the patient;

FIG. 107 is a perspective view of another embodiment of a nasal assemblymounted to a patient's head;

FIG. 107-1 is a perspective view of yet another embodiment of thepresent invention;

FIG. 107-2 is a perspective view of yet another embodiment of thepresent invention;

FIGS. 107A to 107C illustrate yet another alternative embodiment of thepresent invention;

FIGS. 107D and 107E illustrate still another embodiment according to thepresent invention;

FIG. 107F illustrates another alternative embodiment of the presentinvention;

FIGS. 107G and 107H illustrate another alternative embodiment of thepresent invention;

FIG. 107I illustrates still another embodiment of the present invention;

FIG. 107J illustrates yet another alternative embodiment of the presentinvention;

FIGS. 107K and 107L illustrate yet another embodiment of the presentinvention;

FIGS. 107M to 107Q illustrate cross-sections of alternative nozzlesaccording to the present invention;

FIG. 107R illustrates a perspective view of two nozzles like the nozzleshown in FIG. 107Q;

FIG. 108 is a perspective view of yet another embodiment of a nasalassembly;

FIGS. 108A and 108B illustrate a tube retainer according to anembodiment of the present invention;

FIG. 108C illustrates another tube retainer according to an embodimentof the present invention;

FIG. 109 is an isometric view illustrating a portion of the nasalassembly shown in FIG. 108 ;

FIG. 110 is a cross-sectional view of a portion of a nasal assemblyaccording to the present invention;

FIGS. 110-1 and 110-2 illustrate cross-sectional views of a ventaperture according to the present invention;

FIG. 110A is a partial enlarged cross-sectional view of the left handside of FIG. 110 ;

FIG. 110B is an partial enlarged cross-sectional view of the right handside of FIG. 110 ;

FIG. 111 is an exploded perspective view showing the interface betweenseal ring and elbow swivel according to an embodiment of the presentinvention;

FIG. 112 is a partial cross-sectional view of a portion of the maskassembly shown in FIG. 108 ;

FIG. 113 illustrates still another embodiment of the present inventionwith an integral plug and seal assembly;

FIGS. 114 to 126 illustrate yet another embodiment of the presentinvention;

FIGS. 127 to 130 illustrate still another embodiment of the presentinvention;

FIGS. 131 to 133 illustrate yet another swivel elbow according to anembodiment of the present invention; and

FIGS. 134 and 135 illustrate further alternative embodiments of thepresent invention.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

The following includes descriptions of several main illustratedembodiments of the present invention. Each illustrated main embodimentincludes features that may be used with and/or in the other embodiments,as would be apparent to those of ordinary skill in the art.

First Illustrated Embodiment

FIG. 1 shows an embodiment of a nasal assembly 10 structured to deliverbreathable gas to nasal passages 12 of a patient's nose 14. The nasalassembly 10 includes a frame 16 and a nozzle assembly 18 that may bepermanently or removably connected to the frame 16. A headgear assembly20 (see FIG. 18 ) is preferably removably attached to connectionassembly 22 to maintain the frame 16 and nozzle assembly 18 in a desiredadjusted position on the patient's face. Inlet conduits (see FIG. 49 forexample) are also removably attached to the frame 16 by a connectionassembly 22 to deliver breathable gas into the frame 16 and nozzleassembly 18 for breathing by the patient. The headgear assembly 20 andinlet conduits are removably attached to the frame 16 by an inletconduit and headgear connection assembly 22. The connection assembly 22includes first connector portions 24 (see FIGS. 2 and 3 ) provided bythe frame 16 and second connector portions 26 adapted to be removablycoupled with the first connector portions 24. The second connectorportions 26 are removably connected to the headgear assembly 20 and theinlet conduits, as will be further discussed.

As shown in FIGS. 2-4 , the frame 16 includes a main body 28 thatprovides a central opening 30 for accommodating the nozzle assembly 18.The frame 16 also includes side frame members 32 provided on eachlateral side of the main body 28. The side frame members 32 arepreferably formed in one piece with the main body 28 of the frame 16. Inthe illustrated embodiment, the frame 16 is a rigid or semi-rigidstructure formed from a polymer material. However, the frame 16 may besemi-rigid to allow flexibility of the frame 16 with respect to thepatient's face in use. The frame 16 may also be semi-rigid in certainregions for customized flex in certain regions of the frame 16.

Each side frame member 32 includes a first connector portion 24 that isintegrally formed therewith. As best shown in FIGS. 2 and 3 , the firstconnector portion 24 includes a connecting section 34 and an indexingsection 36. The connecting section 34 is structured to interlock withthe second connector portion 26 to prevent axial disengagement of thesecond connector portion 26 from the first connector portion 24. Theindexing section 36 is structured to ratchet/detent with the secondconnector portion 26 to allow selective circumferential adjustment ofthe second connector portion 26 with respect to the first connectorportion 24 about an axis during fit whilst remaining “locked” inadjusted position during usage.

Specifically, the connecting section 34 of each side frame member 32includes a series of grooves or slots 37 that separates the connectingsection 34 into a plurality of resiliently flexible arms 38 that arestructured to flex radially inwardly and outwardly. Each arm 38 providesa rib portion 40 at the free end thereof. In use, the rib portions 40 ofthe plurality of arms 38 are adapted to engage with correspondingportions of the second connector portion 26 for coupling the first andsecond connector portions 24, 26 with one another. For example, thefirst and second connector portions 24, 26 interlock with one another toprevent accidental disengagement of the second connector portion 26 fromthe first connector portion 24 if a force is applied to the secondconnector portion 26 axially away from the first connector portion 24.Moreover, the first and second connector portions 24, 26 mate with oneanother to provide a good seal.

The indexing section 36 of each side frame member 32 includes aplurality of teeth 42. The teeth 42 are structured so as to selectivelyengage a tooth 44 provided on the second connector portion 26 (see FIGS.9 and 10 ). As a result, the second connector portion 26 can be rotatedto a desired position with respect to the frame 16. In use, the tooth 44on the second connector portion 26 engages between selective teeth 42provided on the indexing section 36 in the desired position androtationally locks the second connector portion 26 with respect to thefirst connector portion 24 and hence the frame 16. For adjustment, theuser can manually change the position of the tooth 66 and the teeth 42.

In accordance with one embodiment, the teeth 42 of the indexing section36 can be configured so that when a predetermined torque is applied tothe second connector portion 26, the teeth 42 will automatically forcethe tooth 44 of the second connector portion 26 outwardly to allowrotation of the second connector portion 26 until the torque is removedand the teeth 42 reengage with the tooth 44 of the second connectorportion 26. The second connector portion 26 can thus be rotationallyadjusted or indexed with respect to the frame 16 within a predeterminedangle. The angle of available rotational adjustment can be altered asdesired by altering the number and positioning of the teeth 42 on theindexing section 36. The adjustment angle range allows the patient toadjust the position of the nozzle assembly 18 relative to the nose ofthe patient. For optimal positioning, in one preferred embodiment,nozzle assembly 18 is formed from a one part molded silicone piece thatattaches to frame 16.

In the illustrated embodiment, the adjusting or indexing operation isoriented perpendicular to the connecting operation in order to minimizepotential disengagement of the second connector portion 26 from thefirst connector portion 24.

As best shown in FIG. 4 , the main body 28 includes opposing side walls46 that define the central opening 30 for accommodating the nozzleassembly 18. The side walls 46 are adapted to engage with correspondingportions of the nozzle assembly 18 for coupling the nozzle assembly 18and the frame 16 with one another, as will be further discussed.

As shown in FIGS. 5-8 , the nozzle assembly 18 includes a base portion48 and a pair of nozzles 50 attached thereto. The base portion 48 hasside walls 52 adapted to sealingly engage with the side walls 46 of theframe 16 and a central wall 54. The pair of nozzles 50 each have a firstportion 56 and a second portion 58. The first portion 56 is attached tothe central wall 54 of the base portion 48 in communication withrespective outlet openings provided in the central wall 54. The secondportion 58 is structured to sealingly engage with nasal passages 12 ofthe patient's nose 14 in use and to provide a seal between the nasalassembly 10 and the patient's nasal passages 12. When the nozzleassembly 18 is attached to the frame 16, the nozzle assembly 18 and theframe 16 together form a conduit for directing breathable gas to thepatient's nose through the pair of nozzles 50.

In the illustrated embodiment, the nozzle assembly 18 is removablyattached to the frame 16 with a snap, e.g., snap-fit, push-pin fit, orstretch over fit, which allows for simple assembly. For example, theside walls 52 of the base portion 48 may include a rib or groove/recessthat is structured to interlock with a recess/rib provided on respectiveside walls 46 of the frame 16 with a snap-fit. However, the nozzleassembly 18 may be removably attached to the frame 16 in any othersuitable manner, e.g., friction or interference fit and/or a tongue andgroove arrangement, as is known in the art. Alternatively, the nozzleassembly 18 may be rigidly coupled to the frame 16 by an adhesive orfasteners, for example. Also, the nozzle assembly 18 may be formed inone piece with the frame 16, or over-molded. That is, the nozzleassembly and frame may be a one-piece structure with differentthicknesses and hardnesses to add rigidity.

Preferably, the nozzle assembly 18 is flexible, to thereby allowrelative movement between the nozzle assembly 18 and the frame 16, forincreased comfort and accommodation of variations in patient facialfeatures. Moreover, the base portion 48 is structured such that it canexpand and contract to alter a distance between the frame 16 and thepair of nozzles 50, as will be further discussed below. That is, thecentral wall 54 is preferably made of a resilient and/or flexiblematerial structured to deform, e.g., inflate upon introduction ofpressurized gas, from a generally flat configuration to a generallycurved configuration in use to thereby move the nozzles 50 towards thepatient's nose. Other portions of the base portion 48, e.g., side walls52, may be structured to deform/inflate as well.

In the illustrated embodiment, the base portion 48 has a generallydog-bone shape. However, the base portion 48 may have any suitableshape, including shapes to avoid contact with sensitive regions of thepatient's face, e.g., notched base shape, to prevent contact with thepatient's septum or otherwise minimize contact pressure in thesesensitive regions.

As best shown in FIGS. 1, 5, and 6 , the second portion 58 of the nasalassembly is contoured (e.g., tapered, cone-shaped, truncated hollowcone, etc.) with a portion that seals on the underside of the nostrils(e.g., an area about the rim of the nostril openings) and anotherportion that enters into the nasal passage of the patient's nose in use.However, the nozzles 50 may be in the form of nasal prongs, cannula, ornasal puffs, for example, and may sealingly engage with the nasalpassages 12 in any suitable manner. For example, the nozzles 50 may sealwithin the nasal passages 12, against the nasal passages 12, around thenasal passages 12, or combinations thereof. The nozzles 50 may becontoured to match the interior anatomical profile of the patient'snose. Moreover, different size and/or shape nozzles, e.g., small,medium, and large, may be provided to accommodate a range of patient'snoses.

In the illustrated embodiment, the first portion 56 of the nozzles 50have a reduced cross-section with respect to the second portion 58 toallow the nozzles 50 to move relative to the base portion 48, and hencethe frame 16, for increased comfort and accommodation of variations inpatient facial features.

In one embodiment, the nasal assembly 10 uses patient-customized nozzleswhich may be removably mounted to the base portion 48 or the frame 16.In a preferred form, the nozzles are constructed from a substantiallyflexible polymer material, such as a silicone elastomer. A unique nozzlecan be made match each patient's nose by first scanning their nose,either in situ or remotely, and then using the data for manufacture ofthe interface, for example, a mold maker. Scanning can be done usingeither non-contact or contact methods. Non-contact, for examplephotographically, or by physical contact with a probe or by collectingan impression of the inside of the nares of the desired contactinterface. Once a pair of suitable nozzles are made, they are sent tothe customer to be fitted to a patient. Advantage of the pre-formed orcustomized shape is that cross-sectional area may be maximized to reduceflow impedance. Also, the use of pre-formed shapes improves comfort andincreased stiffness materials such as semi-rigid plastics may be usedthat have greater resistance to distorting, thus minimizing nozzledistortion of the patient's nares. Further, rigid plastics may be usedthat allows thin wall sections and allows flexibility of the nozzle dueto its connection to the base portion 48, e.g., the base portion 48 issoft and compliant.

In the illustrated embodiment, the nozzles 50 are molded in one piecewith the base portion 48 from deformable and inflatable materials. Thenozzles 50 and base portion 48 may be constructed from a soft, flexible,skin-compatible material such as silicone. The nozzles 50 and baseportion 48 may be formed, for example, in an injection, compression,and/or transfer molding process as is known in the art.

However, the nozzles 50 and base portion 48 may be formed with anysuitable material and may be formed by any suitable process. Forexample, the base portion 48 and nozzles 50 may be formed separately andpermanently attached to one another with an adhesive and/or mechanicalfasteners, for example. Alternatively, the base portion 48 and nozzles50 may be formed separately and removably attached to one another.

As aforesaid, second connector portions 26 are provided to removablyconnect the headgear assembly 20 and the inlet conduits with the frame16. As shown in FIGS. 9 and 10 , each second connector portion 26 is aunitary polymeric piece (e.g., silicone) formed by injection molding,compression molding, or blow-molding, for example. Each second connectorportion 26 includes a main body having a front portion 60 and a rearportion 62. The front portion 60 is interlocked with the first connectorportion 24 provided on the frame 16 and the rear portion 62 is removablyconnected to the headgear assembly 20 and the inlet conduits. The frontand rear portions 60, 62 are angled with respect to one another suchthat the second connector portions 26 follow the contour of thepatient's face in use, as shown in FIG. 1 .

Specifically, the front portion 60 provides a generally cylindricalconduit 64 having a recess 66 on an inner surface thereof. The recess 66is adapted to receive the rib portions 40 of the plurality of arms 38 onthe first connector portion 24. That is, the plurality of arms 38 areforced towards one another as the first connector portion 24 is insertedinto the conduit 64 of the second connector portion 26. Once the ribportions 40 of the arms 38 reach the recess 66, the arms 38 can springoutwardly into the recess 66 to provide an interlocking engagementbetween the first and second connector portions 24, 26. To disengage thesecond connector portion 26 from the frame 16, the patient simply pullsthe second connector portion 26 axially outwardly from the frame 16 withsufficient force to release the rib portions 40 from the recess 66.

The front portion 60 also provides a cross-bar 68 that provides thetooth 44 of the second connector portion 26. As discussed above, thetooth 44 engages the plurality of teeth 42 provided by the firstconnector portion 24 to allow selective rotational adjustment of thesecond connector portion 26 with respect to the first connector portion24 and hence the frame 16. The cross bar 68 acts as a leaf spring toresiliently bias the tooth 44 into engagement with the teeth 42 of thefirst connector portion 24.

As shown in FIGS. 9 and 10 , the rear portion 62 of the second connectorportion 26 includes a cross-bar 70 that forms an opening through which astrap of the headgear assembly 20 may pass and be removably connected.However, the cross-bar 70 may be configured to provide more than oneopening for connection to the headgear assembly 20. For example, asshown in FIGS. 11 and 12 , the second connector portion 26′ includes across-bar 71 that provides a pair of openings through which a pair ofstraps of the headgear assembly 20 may pass and be removably connected.

The rear portion 62 also provides an elongated conduit 72 adapted to beconnected to an inlet conduit that delivers breathable gas to the frame16 and nozzle assembly 18. In the illustrated embodiment, the conduit 72of the rear portion 62 has a different cross-sectional shape than theconduit 64 of the front portion 60 to facilitate connection to the inletconduit. However, the conduits 72, 64 of the rear and front portions 62,60, respectively, may have similar cross-sectional areas.

FIGS. 13 and 14 schematically illustrate the routing of on of the firstpair of inlet conduits 74 and one of the second pair of inlet conduits76 of the nasal assembly 10. First ends of the first pair of conduits 74are connected to respective conduits 72 of the second connector portions26. Second ends of the first pair of conduits 74 are connected torespective first ends of the second pair of inlet conduits 76. Secondends of the second pair of inlet conduits are connected to a pressurizedsupply that supplies pressurized breathable gas. As a result,pressurized gas can pass through the first and second pairs of inletconduits 74, 76 into the frame 16 and base portion 48, and through thenozzles 50 for breathing by the patient. As shown in FIG. 1 , the frame16 includes an exhaust vent 78 that protrudes slightly outwardly fromthe frame 16 and includes a series of openings for CO₂ washout.

As schematically shown in FIG. 13 , the first and second pairs of inletconduits 74, 76 may be routed to extend upwardly over the head of thepatient. For example, in FIG. 13 , the first pair of inlet conduits 74may have a length of about 120-160 mm, preferably about 140 mm and thesecond pair of inlet conduits 76 may have a length of about 160-200 mm,preferably about 180 mm. However, other length dimensions may be used aswell. In the illustrated embodiment, the first pair of inlet conduits 74are angled about 30° from horizontal and the second pair of inletconduits 76 are angled about 90° from horizontal, or about 60° from thefirst pair of inlet conduits 74. However, the first and second pairs ofinlet conduits 74, 76 may have any suitable length and may be routed inany suitable manner to extend upwardly over the head of the patient.

Alternatively, as schematically shown in FIG. 14 , the first and secondpairs of inlet conduits 74, 76 may be routed to extend downwardly underthe chin of the patient. For example, in FIG. 14 , the first pair ofinlet conduits 74 may have a length of about 40-80 mm, preferably about60 mm and the second pair of inlet conduits 76 may have a length ofabout 180-220 mm, preferably about 200 mm. In the illustratedembodiment, the first pair of inlet conduits are angled about −20° to40° from horizontal, preferably about 30° from horizontal and the secondpair of inlet conduits 76 are angled about −90° from horizontal, orabout −120° from the first pair of inlet conduits 74. However, the firstand second pairs of inlet conduits may have any suitable length and maybe routed in any suitable manner to extend upwardly over the head of thepatient.

FIGS. 15 and 16 illustrate embodiments of connectors structured tointerconnect the second ends of the first pair of conduits 74 withrespective first ends of the second pair of inlet conduits 76. Theconnector 80 shown in FIG. 15 is suitably angled to route the conduits74, 76 upwardly over the head of the patient. The connector 82 shown inFIG. 16 is suitably angled to route the conduits 74, 76 downwardly underthe chin of the patient.

FIG. 17 illustrates a flow generator connector 84 structured tointerconnect the second ends of the second pair of inlet conduits 76with a pressurized supply. Specifically, the flow generator connector 84includes a first conduit 86 structured to connect to one of the secondpair of inlet conduits 76 and a second conduit 88 structured to connectto the other of the second pair of inlet conduits 76. The flow generatorconnector 84 includes a third conduit 90 structured to connect to aconduit that is connected to the pressurized supply. The third connector90 may include a swivel mechanism or flexible joint to allow relativemovement between the flow generator connector 84 and the conduitassociated with the pressurized supply.

In the illustrated embodiment, the inlet conduits 74, 76 provide asingle air flow channel. However, the conduits 74, 76, connectorportions 24, 26, and connectors 80, 82, 84 may be structured to providemore than one air flow channel.

The inlet conduits 74, 76 may be manufactured in any suitable manner.For example, the conduits 74, 76 may be extruded or the conduits may beinjection molded. Also, the inlet conduits 74, 76 may be structured fromany suitable polymeric material such as silicone or a thermoplasticelastomer, such as Krayton®, for example.

Also, the inlet conduits 74, 76 may be formed of crush-resistant,anti-crush or anti-kinking tubing such as that disclosed in U.S. Pat.No. 6,044,844, the entirety of which is incorporated herein byreference.

The inlet conduits 74, 76 and respective connector portions 24, 26and/or connectors 80, 82, 84 may be retained with a friction-type fit,mechanical fasteners, adhesive, co-molded, insert molded, or any othersuitable means.

In use, pressurized gas enters through connector 90 of the flowgenerator connector 84 and proceeds through the second set of inletconduits 76 into the first set of inlet conduits 74 and into both sideframe members 32 of the frame 16. Air passes through the frame 16, intothe base portion 48 and nozzles 50, and into the nasal passages 12 ofthe patient. Exhaust gasses from the patient's nose can exit through theexhaust vent 78 provided in the frame 16.

The headgear assembly 20 is removably attached to second connectorportion 26 attached to the frame 16 to maintain the frame 16 and nozzleassembly 18 in a desired adjusted position on the patient's face. Asshown in FIG. 18 , the headgear assembly 20 includes two side portions92 with a rear portion 94 connecting the side portions 92. Each sideportion 92 comprises a side strap 96. The rear portion 94, whichinterconnects the two side portions 92, includes an upper strap 98 thatpasses over the top of the patient's head and a rear strap 100 thatpasses around the rear portion of the patient's head. However, theheadgear assembly may be permanently attached to the frame.

Each side strap 96 is removably connected to the second connectorportion 26. Specifically, the end portion of each side strap 96 has areduced width that enables the side strap 96 to be wrapped around thecross-bar 70 provided on the second connector portion 26. Fastening ofthe side straps 96 to respective cross-bars 70 may be assisted by use ofa hook and loop material, such as Velcro®. Thus, the side straps 96 maybe adjusted with respect to the second connector portion 26 for properfit.

The upper strap 98 and rear strap 100 are removably connected to theside straps 96 by buckles 102 provided on the side straps 96. Thebuckles 102 can be attached to the side straps 96 with adhesives,stitching and/or other known manners. In the illustrated embodiment, thebuckles 102 includes a single cross-bar to enable the upper and rearstraps 98, 100 to be coupled therewith. However, any other suitablebuckle arrangement may be provided to interconnect the side straps 96with the upper and rear straps 98, 100.

The straps 96, 98, 100 of the headgear assembly 20 may be constructedfrom a soft, flexible composite material. For example, the straps 96,98, 100 may include two layers of material with one of the layers madeof a fabric material and the other of the layers made of a polymericmaterial. Also, the headgear assembly 20 may include one or morestiffeners attached thereto in order to add to the rigidity of theheadgear assembly 20 in certain planes and directions, which wouldassist in stabilizing the nasal assembly 10 on the head of the patientduring use.

Further, the headgear assembly 20 may include any number of straps tosupport the nasal assembly 10 on the patient's head. For example, eachof the side straps 96 may include a pair of straps to be used with thesecond connector portion 26′ shown in FIGS. 11 and 12 . Alternatively,the headgear assembly 20 may be constructed as a one piece structure.

As best shown in FIG. 1 , the base portion 48 extends outwardly from theframe 16 to provide additional surface area or footprint area. As airunder pressure enters the frame 16, the base portion 48 inflates, whichmoves the nozzles 50 into sealing engagement with the nasal passages 12of the patient. For example, expansion of the base portion in thedirection of the nostrils causes the nozzles to move into sealingengagement with the nasal passages.

Also, a portion of the sealing force may be provided by the firstportion 56, which may be pre-loaded, like a spring, against thepatient's nostril.

That is, the base portion 48 is structured such that it can expand andcontract to alter a distance between the frame 16 and the nozzles 50.The base portion 48 moves the nozzles 50 between a first position inwhich the nozzles 50 are adjacent to the nasal passages 12 of thepatient and a second position in which the nozzles 50 are moved intosealing engagement with the nasal passages 12 of the patient.Specifically, in an un-inflated condition, the nozzles 50 are spacedfrom the nasal passages 12 of the patient or in light contact therewith.When the nasal assembly 10 is pressurized by a gas, the base portion 48is inflated and moves the nozzles 50 into sealing engagement with thenasal passages 12 of the patient to form a seal between the nasalassembly 10 and the patient's nasal passages 12. As the gas pressure isincreased, the force applied to the underside of the nasal passages isincreased through the base portion 48.

The base portion 48 provides additional surface area or footprint areato the frame 16, which in turn provides an additional force on thenozzles 50 which increases the sealing efficiency of the nozzles 50.That is, the base portion 48 is configured and positioned to force thenozzles 50 into contact with the patient's nose. The force or pressureon the patient's nose is proportional to: (a) the pressure in the frame16 and nozzle assembly 18; (b) additional surface area of the baseportion 48; and/or (c) the preload from materials and geometry ofnozzles 50 or base portion 48, including central wall 54 and firstportion 56 of the base portion 48. Thus, the surface area of the baseportion 48 may be varied, e.g., to vary the force or pressure applied tothe patient's nose.

The side walls 52 of the base portion 48 may act as a spring structureto provide a component of force on the patient's face through thenozzles 50. The force may be tailored by adjusting the thickness of theside walls 52. Moreover, the thickness of the side walls 52 may bevaried in conjunction with the additional surface area provided by thebase portion 48. Thus, the force provided by the base portion 48 alongwith the air pressure provides an effective sealing force against thenasal passages 12 of the patient.

The base portion 48 reduces the headgear assembly tension required toachieve a suitable seal. That is, the sealing force applied to thepatient's nose may be provided by the base portion 48, preload and/orair pressure, and not by the tension from the headgear assembly 20. Thisimproves patient comfort as well as sealing properties.

Accordingly, it is desirable when adjusting the headgear assembly 20 tobring the nozzles 50 only near or in very light contact with thepatient's nose. In this way, the base portion 48 is not compressedsubstantially. In use, contact will need to be sufficient for seal.

The base portion 48 also provides a decoupling joint between the frame16 and the nozzles 50, thus allowing some relative movement between thenasal assembly 10 and the user's face. As a result, the nozzles 50 canaccommodate small variations in the shape of the patient's nasalfeatures without undue force, and can account for small movement of thenasal assembly 10 relative to the patient's nose during use, whilemaintaining an effective seal.

Moreover, the connection assembly 22 including the first and secondconnector portions 24, 26 enables the position of the nozzles 50 to beeasily adjusted with respect to the patient's nose. Specifically, thepatient can rotate the frame 16 with respect to the headgear assembly 20to adjust the positioning of the nozzles 50.

Also, the base portion 48 need not be a single base form discussedabove, but can have alternative configurations. For example, the baseportion 48 may be in the form of two or more base portions provided inseries.

As shown in FIGS. 5 and 6 , end portions of the base portion 48 areangled with respect to one another so as to angle the nozzles 50attached thereto with respect to one another. This angle, also referredto as an alar angle, can be adjusted to accommodate different shapednoses of patients. For example, the nozzle assembly 10 shown in FIGS. 5and 6 has an alar angle in the range of 135-155°, preferably about 145°,to accommodate a substantially flat nose (see FIG. 19 ). Alternatively,the alar angle may be in the range of 70-90°, preferably about 80°, toaccommodate a substantially pointed or steep nose (see FIG. 20 ).However, the alar angle may have any suitable size to accommodate anyshape nose. Movement of the nozzles helps accommodate steeper noses.

As shown in FIG. 21 , the sealing zone of the nozzle 50 may extend at anangle from about half the height of the nozzle 50. In the illustratedembodiment, the nozzle 50 has a height of about 9 mm. However, thenozzle 50 may have any suitable height and may provide any suitablesealing zone.

The nozzles 50 are appropriately spaced with respect to one another onthe base portion 48. The spacing is based on the size of the nozzles 50and the available space on the base portion 48.

The size of the nozzles 50 is based on the patient's nostrilcircumference. In one embodiment, ellipse ratios may be used todetermine nozzle geometry (see FIG. 22 ). For example, an ellipse ratioof 0.7 (Average+1 Standard Deviation) may be used to determine nozzlegeometry. As shown in FIG. 23 , the base major axis of the nozzle may bedefined by measurement from the center of a nostril to the upper lip. Asshown in FIG. 24 , the base minor axis of the nozzle may be defined bythe maximum space available between nozzles. However, any other suitablemethod may be used to determine the size of the nozzles.

The above-noted alar angle, sealing zone, spacing between nozzles, andsize of the nozzles may be determined so that a wide range of patientscan be accommodated. Also, different size nasal assemblies, e.g., small,medium, and large, may be provided to accommodate different sizepatients. However, any other suitable measurements and methods may beused to provide a nasal assembly that fits the widest range of patients.

One aspect of the invention relates to a nasal assembly that providesseparate sealing and stability forces. That is, the nasal assemblies arestructured such that the stability forces that act to maintain the nasalassembly on the patient's face are separated or at least betterdistinguished from the sealing forces that act to maintain a sealbetween the nasal assembly and the patient's face. In use, the sealingforces act on more sensitive regions of the patient's face, e.g., nose,and the stability forces act on less sensitive regions of the patient'sface, e.g., upper lip, cheeks and back of the patient's head. Moreover,the stability forces tend to be higher than the sealing forces. Thus,the nasal assembly is structured such that the higher stability forcesare substantially separated from the lower sealing forces to improvepatient comfort.

Specifically, the nasal assembly is structured such that stabilityforces applied by the headgear assembly are distributed to the back ofthe patient's head, the patient's cheeks, and the patient's upper lip tomaintain the nasal assembly on the patient's face in use. The nasalassembly includes the nozzle assembly structured to apply sealing forcesto nasal passages of the patient's nose in use. Features of the headgearhave been designed to achieve substantially independent adjustment ofsealing and stability forces. Thus, the higher stability forces do noteffect the more sensitive regions of the patient's face, e.g., nose, asmuch.

Another aspect of the invention relates to the association between thenozzles and the base portion to apply a force to the patient's face.Specifically, the base portion is structured to apply a component offorce to the patient's face and the nozzles are structured to apply acomponent of force to the patient's face.

As shown in FIG. 1 , for example, the base portion may have asubstantially rigid structure such that it applies a relatively smallcomponent of force on the patient's face. That is, the base portion maynot be substantially inflatable or expandable when pressurized by a gas.In contrast, the nozzles may have a flexible structure such that theyprovide a relatively larger component of force on the patient's face.That is, the first portion 56 of the nozzles 50 may act as a springstructure, e.g., spring-loaded or resilient, to provide a component offorce on the patient's face through the nozzles 50. By spring-loaded, itis meant that the nozzles apply a predetermined force against the user'snasal sealing area, for sealing purposes. Preferably, nozzles arepreloaded before introducing pressurized gas to provide a sealing forcewith the user. As a result, the base portion and nozzles togetherprovide a force to provide a seal between the nasal assembly and thepatient's nasal passages.

Alternatively, the base portion may have a flexible structure such thatit applies a relatively large component of force on the patient's facewhen inflated. In contrast, the nozzles may have a more rigid structuresuch that they apply a relatively smaller component of force on thepatient's face. As a result, the base portion and nozzles togetherprovide a force to provide a seal between the nasal assembly and thepatient's nasal passages.

Thus, the nozzle assembly may be structured such that the nozzles arespring-loaded or resilient to apply a sufficient component of force forsealing. Thus, the base portion can be structured more rigidly to applya smaller component of force for sealing. Alternatively, the nozzleassembly may be structured such that the base portion is sufficientlyexpandable to apply a sufficient component of force for sealing and thenozzles can be structured more rigidly to apply a smaller component offorce for sealing. Alternatively, the nozzles may be substantiallyrigid, e.g., where the nozzles are tailored for a particular user. Thisalternative can be combined with the earlier embodiment (relating rigidbase portions and spring-loaded (e.g. preloaded) nozzles). In thisevent, the base of the nozzle may be structured to provide a variableamount of preload, and the sealing portion of the nozzle, preferablytailored to the user, may be relatively more rigid. Also, the nozzleassembly may be structured such that the base portion and nozzlesprovide substantially similar components of force for sealing.

Second Illustrated Embodiment

FIGS. 25-37 illustrate another embodiment of a nasal assembly, indicatedas 210. As best shown in FIGS. 25-27 , the nasal assembly 210 includes aframe 216 and a nozzle assembly 218 that is removably connected to theframe 216. A headgear assembly 220 (see FIG. 37 ) is removably attachedto the frame 216 to maintain the frame 216 and nozzle assembly 218 in adesired adjusted position on the patient's face. Inlet conduits 274 (seeFIGS. 36 and 37 ) are also removably attached to the frame 216 todeliver breathable gas into the frame 216 and nozzle assembly 218 forbreathing by the patient. The headgear assembly 220 and inlet conduits274 are removably attached to the frame 216 by an inlet conduit andheadgear connection assembly 222. The connection assembly 222 includesfirst connector portions 224 (see FIGS. 28 and 29 ) provided by theframe 216 and second connector portions 226 adapted to be removablycoupled with the first connector portions 224. The second connectorportions 226 are removably connected to the headgear assembly 220 andthe inlet conduits 274, as will be further discussed.

As shown in FIGS. 28 and 29 , the frame 216 includes a main body 228that provides a central opening 230 for accommodating the nozzleassembly 218. The frame 216 also includes side frame members 232provided on each lateral side of the main body 228. Each side framemember 232 includes a first connector portion 224 that is integrallyformed therewith. The first connector portion 224 is in the form of aconduit 264 having a recess 266 on an inner surface thereof. The frame216 also includes a series of openings 278 for CO₂ washout.

As shown in FIGS. 25-27 and 30-31 , the nozzle assembly 218 forms aconduit that includes a main body 219 and opposing end portions 221(only half of the nozzle assembly 218 is shown in the figures). As bestshown in FIG. 27 , the end portions 221 are stretched over the sideframe members 232 of the frame 216 with the main body 219 in coveringrelation to the main body 228 and central opening 230 of the frame 216.When the nozzle assembly 218 is attached to the frame 216, the frame 216adds rigidity to the relatively flexible nozzle assembly 218.

The main body 219 of the nozzle assembly 218 includes a gusset portion248 and a pair of nozzles 250 attached thereto. The nozzles 250 may bedesigned and structured in a similar manner to the nozzles 50 describedabove. The main body 219 of the nozzle assembly also includes a seriesopenings 223 that align with the series of openings 278 provided on theframe 216 for CO₂ washout.

As shown in FIGS. 32-34 , the second connector portion 226 includes amain body having a front portion 260 and a rear portion 262. The frontportion 260 includes a plurality of resiliently flexible arms 238 thatare structured to flex radially inwardly and outwardly. Each arm 238provides a rib portion 240 at the free end thereof. In use, the ribportions 240 of the plurality of arms 238 are adapted to engage withinthe recess 266 of the first connector portion 224 for coupling the firstand second connector portions 224, 226 with one another. In contrast tothe connection assembly 22 described above, the connection assembly 222does not provide an indexing section. Thus, the second connector portion226 may rotate with respect to the first connector portion 224 for aninfinite amount of settings for alignment of the nozzles 250 withrespect to the nasal passages of the patient. The settings may be lockedby way of friction, for example.

The rear portion 262 of the second connector portion 226 includes across-bar 270 that forms an opening through which a strap of theheadgear assembly 220 may pass and be removably connected. The rearportion 262 also provides a pair of conduits 272 adapted to be connectedto an inlet conduit that delivers breathable gas to the frame 216 andnozzle assembly 218.

As shown in FIG. 36 , the nasal assembly 210 includes a pair of inletconduits 274 (only one of the inlet conduits 274 being visible in FIG.36 ). First ends of the pair of conduits 274 are connected to respectivesecond connector portions 226 connected to the frame 216. Second ends ofthe pair of conduits 274 are connected to a pressurized supply thatsupplies pressurized breathable gas. As shown in FIGS. 36 and 37 , thepair of inlet conduits 274 are routed to extend upwardly over the headof the patient. However, the pair of inlet conduits 274 may be routed inany suitable manner, e.g., routed to extend downwardly under the chin ofthe patient.

As a result, pressurized gas can pass through the pair of inlet conduits274 into the frame 216 and nozzle assembly 218, and through the nozzles250 for breathing by the patient.

FIG. 35 illustrates a flow generator connector 284 structured tointerconnect the second ends of the pair of inlet conduits 274 with apressurized supply. Specifically, the flow generator connector 284includes a pair of first conduits 286 structured to connect to one ofthe pair of inlet conduits 274 and a pair of second conduits 288structured to connect to the other of the pair of inlet conduits 274.The flow generator connector 284 includes a third conduit 290 structuredto connect to a conduit that is connected to the pressurized gas, air,or fluid supply. The third connector 290 may include a swivel orflexible joint mechanism to allow relative movement between the flowgenerator connector 284 and the conduit associated with the pressurizedsupply. Also, the third connector 290 may include a ball and socketjoint so that when the third connector 290 is on top of the patient'shead in an over the head configuration, the tube pull is minimized.

In the illustrated embodiment, the inlet conduits 274 provide a dual airflow channel with a central support wall to prevent kinking andocclusion. However, the conduits 274, connector portions 224, 226, andconnector 284 may be structured to provide one air flow channel or morethan two air flow channels.

The headgear assembly 220 is removably or fixedly attached to secondconnector portion 226 attached to the frame 216 to maintain the frame216 and nozzle assembly 218 in a desired adjusted position on thepatient's face. As shown in FIG. 37 , the headgear assembly 220 includestwo side portions 292 (only one of the side portions 292 being visiblein FIG. 37 ) with a rear portion 294 connecting the side portions 292.Each side portion 292 comprises a side strap 296. The rear portion 294,which interconnects the two side portions 292, includes an upper strap298 that passes over the top of the patient's head and a rear strap 299that passes around the rear portion of the patient's head. Also shown inFIG. 37 is an intermediate strap connector 295 that is connected to theinlet conduit 274 and has a hole 297 to which the rear strap 299 isconnected. Upper and rear strap 298, 299 can be adjusted for fit and canbe a single strap or loop. Also, the headgear assembly may bepermanently attached to the frame.

Each side strap 296 has a reduced width that enables the side strap 296to be wrapped around the cross-bar 270 provided on the second connectorportion 226. Fastening of the side straps 296 to respective cross-bars270 may be assisted by use of a hook and loop material, such as Velcro®.Thus, the side straps 296 may be adjusted with respect to the secondconnector portion 226 for proper fit.

Openings or buckles are provided on the side straps 296 to enable theupper and rear straps 298, 299 to be coupled therewith. However, theheadgear assembly 220 may include any number of straps to support thenasal assembly 210 on the patient's head. Alternatively, the headgearassembly 220 may be constructed as a one piece structure.

As shown in FIG. 37 , the headgear assembly 220 includes a retainingstrap 291 to hold the flow generator connector 284 and the inletconduits 274 in a position over the head of the patient. The headgearassembly 220 also includes retaining prongs 293 to hold the inletconduits 274 adjacent to the headgear assembly 220 as they extendupwardly over the head of the patient.

Similar to the nasal assembly 10 described above, the force provided bythe gusset portion 248 along with the air pressure provides an effectivesealing force against the nasal passages 12 of the patient. Thus, thegusset portion 248 reduces the headgear assembly tension required toachieve a suitable seal. Also, the position of the nozzles 250 may beadjusted with respect to the user's nose to improve patient comfort.

As shown in FIG. 25 , for example, the gusset portion 248 has a flexiblestructure such that it applies a relatively large component of force onthe patient's face when inflated. In contrast, the nozzles have a morerigid structure such that they apply a relatively smaller component offorce on the patient's face. That is, the first portion of the nozzlesmay have less of a spring-load to provide a relatively small componentof force on the patient's face through the nozzles. As a result, thegusset portion and nozzles together provide a force to provide a sealbetween the nasal assembly and the patient's nasal passages.

Third Illustrated Embodiment

FIGS. 38-51 illustrate another embodiment of a nasal assembly, indicatedas 310. As best shown in FIGS. 38, 39, and 43 , the nasal assembly 310includes a frame 316 and a nozzle assembly 318 that is removablyconnected to the frame 316. A headgear assembly 320 is removablyattached to the frame 316 to maintain the frame 316 and nozzle assembly318 in a desired adjusted position relative to the patient's face. Inletconduits 374 are also removably attached to the frame 316 to deliverbreathable gas into the frame 316 and nozzle assembly 318 for breathingby the patient. The headgear assembly 320 and inlet conduits 374 areremovably attached to the frame 316 by an inlet conduit and headgearconnection assembly 322. The connection assembly 322 includes firstconnector portions 324 (see FIGS. 40 and 43 ) provided by the frame 316and second connector portions 326 adapted to be removably coupled withthe first connector portions 324. The second connector portions 326 areremovably connected to the headgear assembly 320 and the inlet conduits374, as will be further discussed.

As shown in FIG. 40 , the frame 316 includes a main body 328 thatprovides a central opening 330 for accommodating the nozzle assembly318. The frame 316 also includes side frame members 332 provided on eachlateral side of the main body 328. Each side frame member 332 includes afirst connector portion 324 that is integrally formed therewith. Thefirst connector portion 324 is in the form of a conduit 364 having arecess 366 (see FIG. 43 ) on an inner surface thereof.

As shown in FIG. 41 , the nozzle assembly 318 forms a conduit thatincludes a main body 319 and opposing end portions 321. As best shown inFIGS. 42, 43, and 44 , the end portions 321 are stretched over the sideframe members 332 of the frame 316 with the main body 319 in coveringrelation to the main body 328 and central opening 330 of the frame 316.When the nozzle assembly 318 is attached to the frame 316, the frame 316and nozzle assembly 318 form a conduit for delivering breathable gas tothe patient's nose. Also, the frame 316 adds rigidity or structuralintegrity to the relatively flexible nozzle assembly 318.

As shown in FIGS. 43 and 44 , the main body 319 of the nozzle assembly318 includes a base portion 348 and a pair of nozzles 350 attachedthereto. The nozzles 350 may be designed and structured in a similarmanner to the nozzles 50 described above. The main body 319 of thenozzle assembly 318 also includes one or more openings 323 (e.g., seeFIGS. 39 and 41 ) for CO₂ washout.

As shown in FIGS. 38B and 43 , the second connector portion 326 includesa main body having a front portion 360 and a rear portion 362. The frontportion 360 includes a rib portion 340. In use, the rib portion 340 isadapted to engage within the recess 366 of the first connector portion324 for coupling the first and second connector portions 324, 326 withone another. Similar to the connection assembly 222 described above, thesecond connector portion 326 may rotate with respect to the firstconnector portion 324 for an infinite amount of settings for alignmentof the nozzles 350 with respect to the nasal passages of the patient.The setting may be optionally locked by friction, for example.

As shown in FIGS. 38 and 38B, the rear portion 362 of the secondconnector portion 326 includes an opening 370 through which a strap ofthe headgear assembly 320 may pass and be removably connected. As shownin FIG. 38B, the rear portion 362 also provides a pair of conduits 372adapted to be connected to an inlet conduit that delivers breathable gasto the frame 316 and nozzle assembly 318.

As shown in FIGS. 38, 39, and 45 , the nasal assembly 310 includes apair of inlet conduits 374. First ends of the pair of conduits 374 areconnected to respective second connector portions 326 connected to theframe 316. Second ends of the pair of conduits 374 are connected to apressurized supply that supplies pressurized breathable gas. As shown inFIG. 45 , the second connector portions 326 may be rotated with respectto the first connector portions 324 to route the pair of inlet conduits374 upwardly over the head of the patient or downwardly under the chinof the patient, for example.

As a result, pressurized gas can pass through the pair of inlet conduits374 into the frame 316 and nozzle assembly 318, and through the nozzles350 for breathing by the patient.

FIGS. 45, 47, and 48 illustrate an angle connector 384 structured tointerconnect the second ends of the pair of inlet conduits 374 with apressurized supply. As shown in FIG. 47 , the connector 384 may includea pair of double-conduits 386 to connect to respective inlet conduits374. Alternatively, as shown in FIG. 48 , the flow generator connector384 may include a pair of single-conduits 386 to connect to respectiveinlet conduits 374. The end of the dual air flow channel inlet conduit374 may be amended, as shown in FIG. 48 , to facilitate connection withthe connector 384 having a pair of single-conduits 386. Also, the endsof the inlet conduit 374 may include a series of ridges that interlockwith a series of ridges provided on the connector 384 to reliablyconnect the inlet conduits 374 with the connector 384, as shown in FIGS.47 and 48 .

As shown in FIG. 49 , the inlet conduits 374 provide a dual air flowchannel with a central support wall to prevent kinking or occlusion,e.g., anti-crush, and facilitate connection. Also, the inlet conduitsmay be constructed from a harder material, e.g., harder durometersilicone, to prevent kinking or occlusion. However, the conduits 374,connector portions 324, 326, and connector 384 may be structured toprovide one air flow channel or more than two air flow channels. Asshown in FIG. 47B, the inlet conduits 374 may be extruded or otherwisemanufactured in one piece. Alternatively, as shown in FIG. 48B, theinlet conduits 374 may include a plurality of conduits formed byinjection molding, co-molding, or insert molding, and connected to oneanother in any suitable manner, e.g., by connectors and/or otherfasteners such as adhesive, or the entire assembly could be molded inone piece, thereby reducing components and complexity.

The headgear assembly 320 is removably attached to second connectorportion 326 attached to the frame 316 to maintain the frame 316 andnozzle assembly 318 in a desired adjusted position on the patient'sface. As shown in FIGS. 38, 39, and 45 , the headgear assembly 320includes two side portions 392 with a rear portion 394 connecting theside portions 392. Each side portion 392 comprises a side strap 396. Therear portion 394, which interconnects the two side portions 392,includes an upper strap 398 that passes over the top of the patient'shead and a rear strap 399 that passes around the rear portion of thepatient's head. As shown in FIG. 45 , the rear portion 394 may include asecond rear strap 387 to add additional stability.

Each side strap 396 has a reduced width that enables the side strap 396to be wrapped around the opening 370 provided on the second connectorportion 326. Fastening of the side straps 396 to respective openings 370may be assisted by use of a hook and loop material, such as Velcro®.Thus, the side straps 396 may be adjusted with respect to the secondconnector portion 326 for proper fit.

In the illustrated embodiment, the headgear assembly 320 is constructedas a one piece structure. However, the headgear assembly 320 may includea plurality of straps suitably arranged to support the nasal assembly310 on the patient's head. As shown in FIG. 45 , the headgear assembly320 may include retaining straps 393 to hold the inlet conduits 374upwardly over the head of the patient.

FIG. 50 illustrates the nasal assembly 310 about to be engaged withnasal passages 12 of a patient's nose 14. FIG. 51 illustrates the nasalassembly 310 engaged with nasal passages 12 of a patient's nose. Thepatient's upper lip contacts the silicone outer surface of the nozzleassembly 318 to help maintain the nasal assembly 310 in position on thepatient's face.

Similar to the nasal assembly 10 described above, the force provided bythe base portion 348 along with the air pressure provides an effectivesealing force against the nasal passages 12 of the patient. Thus, thebase portion 348 reduces the headgear assembly tension required toachieve a suitable seal. Also, the position of the nozzles 350 may beadjusted with respect to the user's nose to improve patient comfort.

As shown in FIG. 43 , for example, the base portion 348 has a flexiblestructure such that it applies a relatively large component of force onthe patient's face when inflated. In contrast, the nozzles have a morerigid structure such that they apply a relatively smaller component offorce on the patient's face. That is, the first portion of the nozzlesmay have less of a spring-load to provide a relatively small componentof force on the patient's face through the nozzles. As a result, thebase portion and nozzles together provide a force to provide a sealbetween the nasal assembly and the patient's nasal passages.

Further, the base portion 348 may be structured to provide customizedforces in desired directions, e.g., inwardly directed force to assistwith sealing. The base portion 348 may offer greater displacement insome areas that would provide additional forces.

FIG. 46 is a force diagram that illustrates some of the forces that aredeveloped when the nasal assembly 310 is attached to the patient's head.For example, the headgear tension provides a force on the patient's faceand the patient's nose and lip provide forces on the nasal assembly 310.

Fourth Illustrated Embodiment

FIGS. 52-58 illustrate another embodiment of a nasal assembly, indicatedas 410. As best shown in FIGS. 52 and 53 , the nasal assembly 410includes a frame 416 and a nozzle assembly 418 that is removablyconnected to the frame 416. A headgear assembly 420 is removablyattached to the frame 416 to maintain the frame 416 and nozzle assembly418 in a desired adjusted position on the patient's face. Inlet conduits474 are also removably attached to the frame 416 to deliver breathablegas into the frame 416 and nozzle assembly 418 for breathing by thepatient. The headgear assembly 420 and inlet conduits 474 are removablyattached to the frame 416 by an inlet conduit and headgear connectionassembly 422. The connection assembly 422 includes first connectorportions 424 (see FIGS. 55 and 56 ) provided by the frame 416 and secondconnector portions 426 adapted to be removably coupled with the firstconnector portions 424. The second connector portions 426 are removablyor fixedly connected to the headgear assembly 420 and the inlet conduits474, as will be further discussed.

As shown in FIGS. 52 and 54 , the frame 416 includes a main body 428that provides a central opening 430 for accommodating the nozzleassembly 418. The frame 416 also includes side frame members 432provided on each lateral side of the main body 428. Each side framemember 432 includes a first connector portion 424 that is integrallyformed therewith. The first connector portion 424 is in the form ofcross-bar 466 (see FIGS. 55 and 56 ). As best shown in FIG. 54 , themain body 428 includes rim 446 that define the central opening 430.

As shown in FIG. 54 , the nozzle assembly 418 includes a gusset portion448 and a pair of nozzles 450 attached thereto. The gusset portion 448has side walls 452 adapted to sealingly engage with the rim 446surrounding opening 430 of the frame 416. For example, the side walls452 of the gusset portion 448 may include a recess that is structured tointerlock with a respective tab provided on the rim 446 of the frame 416with a snap-fit. However, the nozzle assembly 418 may be removablyattached to the frame 416 in any other suitable manner, such as afriction fit, for example. When the nozzle assembly 418 is attached tothe frame 416, the nozzle assembly 418 and the frame 416 together form aconduit for directing breathable gas to the patient's nose through thepair of nozzles 450.

The nozzles 450 may be designed and structured in a similar manner tothe nozzles 50 described above. The frame 416 may include one or moreopenings (not shown) for exhaled CO₂ washout.

As shown in FIG. 55 , the second connector portion 426 includes a mainbody having a front portion 460 and a rear portion 462. The frontportion 460 includes a pair of arm members 461 having an integral lug463 at a distal end thereof. In use, the arm members 461 are flexedinwardly by the cross-bar 466 of the first connector portion 424 untilthe arm members 461 reach an operative position in which the arm members461 flex back outwardly such that the shoulder of the lug 463 ispositioned to interlock the second connector portion 426 with the firstconnector portion 424 (see FIG. 56 ).

The arm members 461 of the second connector portion 426 may rotate withrespect to the cross-bar 466 of the first connector portion 424. Asshown in FIG. 55 , a protrusion 465 may be provided on the arm members461 that selectively engages within a series of recesses provided on aninner surface of the cross-bar 466 so as to provide a predeterminednumber of settings for alignment of the nozzles 450 with respect to thenasal passages of the patient.

As shown in FIG. 55 , the rear portion 462 provides a pair of conduits472 adapted to be connected to an inlet conduit that delivers breathablegas to the frame 416 and nozzle assembly 418. The rear portion 462 ofthe second connector portion 426 also includes a cross-bar or opening(not shown) through which a strap of the headgear assembly 420 may passand be removably connected.

As shown in FIGS. 52 and 53 , the nasal assembly 410 includes a pair ofinlet conduits 474. First ends of the pair of conduits 474 are connectedto respective second connector portions 426 connected to the frame 416.Second ends of the pair of conduits 474 are connected to a pressurizedsupply that supplies pressurized breathable gas. As shown in FIG. 52 ,the second connector portions 426 may be rotated with respect to thefirst connector portions 424 to route the pair of inlet conduits 474upwardly over the head of the patient or downwardly under the chin ofthe patient, for example.

As a result, pressurized gas can pass through the pair of inlet conduits474 into the frame 416 and nozzle assembly 418, and through the nozzles450 for breathing by the patient.

FIG. 53 illustrates a flow generator connector 484 structured tointerconnect the second ends of the pair of inlet conduits 474 with apressurized supply.

As shown in FIG. 52 , the inlet conduits 474 provide a dual air flowchannel to prevent kinking and facilitate connection. However, theconduits 474, connector portions 424, 426, and connector 484 may bestructured to provide one air flow channel or more than two air flowchannels.

The headgear assembly 420 is removably attached to second connectorportion 426 attached to the frame 416 to maintain the frame 416 andnozzle assembly 418 in a desired adjusted position on the patient'sface. As shown in FIGS. 52 and 53 , the headgear assembly 420 includestwo side portions 492 with a rear portion 494 connecting the sideportions 492. Each side portion 492 comprises a side strap 496. The rearportion 494, which interconnects the two side portions 492, includes anupper strap 498 that passes over the top of the patient's head and arear strap 499 that passes around the rear portion of the patient'shead. However, the headgear assembly may be permanently attached to theframe.

Each side strap 496 has a reduced width that enables the side strap 496to be wrapped around the cross-bar or opening provided on the secondconnector portion 426. Fastening of the side straps 496 to respectivecross-bars or openings may be assisted by use of a hook and loopmaterial, such as Velcro®. Thus, the side straps 496 may be adjustedwith respect to the second connector portion 426 for proper fit.

In the illustrated embodiment, the headgear assembly 420 is constructedas a one piece structure. However, the headgear assembly 420 may includea plurality of straps suitably arranged to support the nasal assembly410 on the patient's head. As shown in FIGS. 52 and 53, the headgearassembly 420 may include retaining straps 493 to hold the inlet conduits474 upwardly over the head of the patient.

FIGS. 57 and 58 illustrate the nasal assembly 410 being engaged withnasal passages 12 of a patient's nose. Similar to the nasal assembly 10described above, the force provided by the gusset portion 448 along withthe air pressure provides an effective sealing force against the nasalpassages 12 of the patient. Thus, the gusset portion 448 reduces theheadgear assembly tension required to achieve a suitable seal. Also, theposition of the nozzles 450 may be adjusted with respect to the user'snose to improve patient comfort.

As shown in FIG. 58 , for example, the gusset portion has asubstantially rigid structure such that it applies a relatively smallcomponent of force on the patient's face when inflated. In contrast, thenozzles have a flexible structure such that they provide a relativelylarger component of force on the patient's face. That is, the firstportion of the nozzles may have a relatively large spring-load toprovide a component of force on the patient's face through the nozzles.As a result, the gusset portion and nozzles together provide a force toprovide a seal between the nasal assembly and the patient's nasalpassages.

Fifth Illustrated Embodiment

FIGS. 59-85 illustrate another embodiment of a nasal assembly, indicatedas 510. The nasal assembly 510 includes a frame 516 and a nozzleassembly 518 that is removably coupled to the frame 516. As best seen inFIG. 61 , the frame 516 includes a pair of first connector portions 524.Referring back to FIG. 59 , a pair of inlet conduits 574 are structuredto deliver breathable gas into the frame 516 and nozzle assembly 518 forbreathing by the patient. The breathable gas is transported from theinlet conduits 574 to the frame 516 and nozzle assembly 518, e.g., via apair of second connector portions 526 and a pair of angle connectors542. The second connector portions 526 are removably and rotatablyconnected to respective first connector portions 524 (FIG. 61 ) of theframe 516. The angle connectors 542 are connected or positioned betweenthe second connector portions 526 and respective inlet conduits 574. Aheadgear assembly 520 is removably connected to (a) the pair of secondconnector portions 526 and/or (b) the angle connectors 542, so as tomaintain the frame 516 and the nozzle assembly 518 in a desired adjustedposition on the patient's face, as will be further discussed.

As shown in FIG. 61 , the frame 516 includes a main body 528 and a sideframe member 532 provided on each lateral side of the main body 528.Each side frame member 532 includes an integrally formed first connectorportion 524. The first connector portion 524 is in the form of a conduit564 having an annular recess 566 on an outer surface thereof. Also, themain body 528 includes an elongated channel 565 on opposing sidesthereof and each side frame member 532 includes an annular channel 567.The channels 565, 567 are structured to receive the ends of the nozzleassembly 518, as will be further discussed.

As shown in FIGS. 61-65 , the nozzle assembly 518 includes a gusset orbase portion 548 and a pair of nozzles 550 attached thereto. The nozzleassembly 518 is coupled with the frame 516 with the pair of nozzles 550structured to sealingly engage with nasal passages of a patient's nosein use and provide a seal between the nasal assembly 510 and thepatient's nasal passages. The nozzles 550 may be designed and structuredin a similar manner to the nozzles 50 described above. Also, the nozzleassembly 518 includes one or more openings 549 for exhaled CO₂ washout.

FIG. 65A is an enlarged view of the nozzle assembly 518 shown in FIG. 65. The nozzle assembly preferably includes an upper contour portion 519that maintains generally the same cross-sectional area through theassembly. Therefore, the assembly generally follows the line of the faceso as not to protrude from the face thereby keeping a low profile.Similarly, FIG. 119 shows a nozzle or cushion assembly 604 thatgenerally follows the contour of the face, from the top view.

The nozzle assembly 518 in FIG. 65A also includes a lower contourportion 521 that generally matches the contour of the face. Further, thenozzle assembly 518 is asymmetric about an axis A to provide a betterfit in comparison with symmetric prior art masks, which may be subjectto creasing or buckling upon distribution to fit the face. The lowercontour 521 is also useful for patients with moustaches.

Forces from the patient interface retainer, e.g., headgear, aretransferred to the face via nozzles 550 as well as lower contour portion521. The increased overall area reduces the force per unit area, tospread the load. The increased overall area also helps to better anchorthe patient interface. The shape of lower contour portion 521 iscustomizable. The lower contour portion 521 may be rigid, semi-rigid,elastic or some combination thereof. The maxilla region of the face canwithstand more pressure without being uncomfortable.

FIG. 65B schematically illustrates the force distribution due to theincreased area. In particular, the region immediately under the nose isonly soft tissue and cartilage.

If the only contact region is the immediate underside of the nose (i.e.,not including maxilla) then to hold a nozzle in place with the leastamount of force would require a resultant force in direction F1. Thismight distort the nose and cause discomfort. If such a strap istightened, it might slip off the front of the head. However, when someof the load is taken by the maxilla (i.e., some force under the nose andsome on the maxilla), the direction of the resultant force can bechanged to F2, the load is spread. Since the maxilla does not move, F2could be higher without causing discomfort. Such an arrangement may bemore tolerant of overtightening. There is also greater ability to cupthe occiput.

In the illustrated embodiment, the nozzle assembly 518 wraps around themain body 528 and each side frame member 532 of the frame 516 and issecured to the frame 516 with a clip 530. In another embodiment, thecushion can be pulled over the frame like a sock. An annular channel 567is formed in each side frame member 532 and side portions 536 of nozzleassembly 518 wrap into channels 567. Specifically, as shown in FIG. 61 ,the nozzle assembly 518 has a generally open-ended tubular configurationwith a longitudinal opening. This configuration provides the nozzleassembly 518 with a pair of opposing spaced apart end portions 534 andside portions 536. When the nozzle assembly 518 is coupled to the frame516, the side portions 536 engage within respective annular channels 567and the end portions 534 engage within respective elongated channels 565on opposing sides of the main body 528, as best shown in FIGS. 64 and 68.

As best shown in FIGS. 62-64 and 66 , the end portions 534 are securedbetween the frame 516 and the clip 530. That is, the end portions 534are secured between respective flanges of opposing channels 565 andflanges of the clip 530. When the nozzle assembly 518 is attached to theframe 516, the nozzle assembly 518 and the frame 516 together form aconduit for directing breathable gas to the patient's nose through thepair of nozzles 550.

The clip 530 may be engaged with the frame 516 and nozzle assembly 518in any suitable manner. For example, as shown in FIGS. 62 and 70 , theclip 530 may be slid onto the frame 516. Alternatively, the clip 530 maybe engaged with the frame 516 with a snap-fit.

As shown in FIG. 59 , the frame 516 is secured to the nozzle assembly518 such that the frame 516 is angled away from an upper lip of thepatient in use. This positions the clip 530 away from the patient suchthat it does not irritate the patient's face. Also, the nozzle assembly518 may be contoured to accommodate a patient's septum in use.

The above-described coupling of the frame 516 and nozzle assembly 518allows the nozzle assembly 518 to be easily removable from the frame 516to facilitate cleaning of the nozzle assembly 518. Moreover, theconfiguration of the nozzle assembly 518 allows interior portions of thenozzle assembly 518 to be accessible for cleaning. The nozzle assembly'sconfiguration also facilitates manufacturing.

However, the nozzle assembly 518 may be removably attached to the frame516 in any other suitable manner. For example, FIGS. 67, 69, and 71illustrate another method of attaching the nozzle assembly to the frame.As illustrated, the frame 616 is structured without channels in the mainbody such that the nozzle assembly 618 wraps around the main body andthe clip 630 is secured between the side frame members of the frame 616to hold the end portions of the nozzle assembly 618.

As shown in FIG. 72 , the second connector portion 526 includes a mainbody having a front portion 560 and a rear portion 562. A groove 561 isprovided adjacent the front portion 560. The front portion 560 includesan annular rib portion 540 (FIG. 73 ). The front portion 560 of thesecond connector portions 526 are stretched over the respective firstconnector portion 524 to provide an interference fit. Also, the ribportion 540 is adapted to engage within the recess 566 of the firstconnector portion 524 for coupling the first and second connectorportions 524, 526 with one another, as shown in FIG. 73 . The secondconnector portion 526 may rotate with respect to the first connectorportion 524 for an infinite amount of settings for alignment of thenozzles 550 with respect to the nasal passages of the patient. Thesetting may be optionally locked by friction, for example. That is, therotatable coupling allows the frame 516 to be rotated with respect tothe second connector portions 526 so as to adjust the position of thenozzles 550 with respect to the patient's nose in use.

The second connector portions 526 may be formed of silicone with ahardness of about 50-60 Shore A hardness. This hardness facilitatesassembly, swiveling movement, and seal with the frame 516. However, thesecond connector portions 526 may be formed of any other suitablematerial and may have any suitable hardness.

Each second connector portion 526 is also formed with a feature thatallows relative movement between the angle connector 542 and the frame516 for different facial widths. In the illustrated embodiment, thefeature is a corrugation 538 in the second angle connector 542. Thisfeature isolates the connection between the second connector portion 526and the frame 516 to prevent detachment. This feature also allows thesecond connector portions 526 to be flexible so as to dampen tube dragforces. Moreover, the second connector portions 526 are flexible withoutobstructing airflow. However, the feature may have any other suitablestructure to provide flexibility.

In the illustrated embodiment, each of the second connector portions 526is provided with or connected to the angle connector 542 (see FIGS.74-76 ) that connects with the respective inlet conduit 574. The secondconnector portions 526 and the angle connectors 542 may be formed in anintegral one piece unit. The rear portion 562 of each second connectorportion 526 includes an interlock in the form of an undercut 544 (FIG.73 ) for engagement with the angle connector 542. The angle connector542 includes a conduit 545 with a shoulder portion 546 that engages theundercut 544 to secure the angle connector 542 to the second connectorportion 526, as can be determined from FIG. 73 , an exploded view priorto connection.

The angle connector 542 includes elongated connectors 552 structured toengage the respective inlet conduit 574. In the illustrated embodiment,the elongated connectors 552 have a tapered configuration to facilitateconnection. Also, the connectors 552 are arranged to wedge the inletconduit 574 therebetween to secure the inlet conduit 574 thereto. Asshown in FIG. 76 , the conduit 545 and elongated connectors 552 of theangle connector 542 are angled about 80° from one another. However, theangle between the conduit 545 and elongated connectors 552 may have anyother suitable dimension.

FIG. 76A illustrates another embodiment of a mask assembly similar tothat shown in FIG. 60 . FIG. 76B is an exploded view of the maskassembly in FIG. 76A. A yoke 580′ in FIGS. 76A and 76B is somewhatdifferent from the yoke 580 shown in FIG. 60 in that the yoke 580′ inFIGS. 76A and 76B has dimensions that are more streamlined, styledand/or optimized for use with the headgear straps. In addition, a secondconnector portion 526′ and elbow connector 542′ in FIG. 76A arestructured to facilitate alignment (or prevent misalignment)therebetween. In particular, as best shown in FIG. 76C, the secondconnector portion 526′ includes a tab 526 a which is intended to bereceived within a key way or recess 542 a of elbow connector 542′. Theelbow connector 542′ also includes a ridge 542 b which receives a tipportion of the tab 526A.

Returning to FIG. 59 , first ends of the pair of conduits 574 areconnected to respective angle connectors 542. Second ends of the pair ofconduits 574 are connected to a flow generator connector 584 coupled orprovided to a swivel 590, which in turn is in communication with apressurized supply that supplies pressurized breathable gas. Asillustrated, the angle connectors 542 route the pair of inlet conduits574 downwardly under the chin of the patient.

As a result, pressurized gas can pass through the pair of inlet conduits574, angle connectors 542, second connector portions 526, frame 516 andnozzle assembly 518, and through the nozzles 550 for breathing by thepatient.

FIGS. 77 and 78 illustrate the flow generator connector 584 structuredto interconnect the second ends of the pair of inlet conduits 574 withthe swivel 590 which is in communication with a pressurized supply. Theflow generator connector 584 includes first elongated connectors 586structured to engage one of the inlet conduits 574 and second elongatedconnectors 588 structured to engage the other of the inlet conduits 574.In the illustrated embodiment, the first and second elongated connectors586, 588 have a tapered configuration, e.g., the tops are formed at anangle, to facilitate connection. Also, the first and second elongatedconnectors 586, 588 are arranged to wedge the respective inlet conduit574 therebetween to secure the respective inlet conduit 574 thereto,e.g., by friction. Moreover, the flow generator connector 584 has ageneral Y-shape with the first elongated connectors 586 angled withrespect to the second elongated connectors 588. The Y-shape of the flowgenerator connector 584 prevents incorrect assembly with the inletconduits 574 and assists in merging the air paths. As shown in FIG. 59 ,a swivel 590 may be attached to the flow generator connector 584 toallow relative movement with respect to the pressurized supply.

As shown in FIG. 79 , each inlet conduit 574 includes a plurality ofchannels. In the illustrated embodiment, each inlet conduit 574 isconstructed with tubing that provides a dual air flow channel to preventor at least reduce kinking and crushing and facilitate connection.However, the conduits 574, angle connectors 542, and connector 584 maybe structured to provide one air flow channel or more than two air flowchannels. The inlet conduits 574 may be formed with silicone and have ahardness of about 50 shore A hardness. However, the inlet conduits 574may be formed of any other suitable material and have any suitablehardness.

The inlet conduits 574 are structured to provide low impedance. In oneembodiment, the inlet conduits 574 provide impedance less than about 3cmH₂O, for a given flow rate. Also, the inlet conduits 574 have a lowprofile. As shown in FIG. 79 , each inlet conduit 574 has a width ofabout 20 mm and a height of about 9.5 mm. However, the inlet conduits574 may have any other suitable shape, size and structure. For example,the inlet conduits 574 may have a substantially D-shaped cross section.The width dimension of 20 mm can be adjusted to change the impedance.For example, if the width is decreased while the height and pressureremain constant, the impedance will be increased, as the cross-sectionalarea decreases. Conversely, if the width is increased, keeping theheight and pressure constant, the impedance can be lowered. The resultis that impedance can be lowered without increasing the height, therebymaintaining a low profile of the inlet conduits 574, such that they areless obtrusive to the patient and/or do not uncomfortably dig into thepatient's face or skin. Other components of the air delivery path, e.g.,the angle connectors 542, have been designed with a view towardsdecreasing impedance. By contrast, impedance of an inlet conduit orangle connector with a round cross section can be similarly lowered byincreasing the diameter of the conduit, but the profile also increaseswith commensurate discomfort to the patient since the conduit may assumea position further outward from the patient's face, and/or the conduitmay be pressed against the patient's face, which decreases comfort andcompliance.

The headgear assembly 520 is removably attached to second connectorportions 526 and angle connectors 542 to retain the second connectorportions 526 on the frame 516. Also, the headgear assembly 520 isstructured to transfer a tube pulling force to the headgear assembly 520or the frame 516, to thereby avoid or reduce the chances that the tubepulling force is applied to the nozzle assembly, which may compromisethe seal between the nozzles and the patient's airways.

As shown in FIGS. 59 and 60 , the headgear assembly 520 includes twoside portions 592 with a rear portion 594 connecting the side portions592. The side portions include side straps and a headgear yoke 580 isattached to each side strap. The headgear yoke 580 acts as a stiffenerto add rigidity to the headgear assembly 520. FIGS. 59 and 60 showslightly different yoke configurations. In FIG. 59 , the yoke is shownas a member which covers at least a portion of flexible straps 598, 599,to add stiffness or rigidity thereto. In FIG. 60 , the yoke 580 is asemi-rigid layer, such as plastic, which is provided to, e.g., sewnonto, the headgear straps 598 and/or 599. The yoke in FIG. 60 may bemore or less co-extensive with the straps 598 and/or 599, depending onthe desired stiffness. The yoke 580 in FIG. 60 is also shown in FIGS.80-82 . The rear portion 594 includes upper straps 598 that pass overthe top of the patient's head and rear straps 599 that pass around therear portion of the patient's head. The upper straps 598 are structuredto adjust the sealing force because they pull the frame 516 up into thepatient's nose. The rear straps 599 are structured to adjust thestability of the nasal assembly 510 because they pull the frame 516 backinto the patient's face on the top lip of the patient.

The upper straps 598 are coupled to one another by a headgear buckle570. The headgear buckle 570 is structured to allow symmetricaladjustment of the headgear assembly 520. Specifically, as shown in FIG.83 , the headgear buckle 570 includes a first locking portion 571 and asecond locking portion 572. The first locking portion 571 is adapted tobe removably and adjustably coupled with one of the upper straps 598extending from one of the headgear yokes 580 and the second lockingportion 572 is adapted to be removably and adjustably coupled with theother of the upper straps 598 extending from the other of the headgearyokes 580. Each of the upper straps 598 may be wrapped around thecross-bar of the associated locking portion 571, 572 of the buckle 570,as best shown in FIG. 59 . A tab 576 is provided on each locking portion571, 572 to facilitate the patient in adjusting headgear tension. Also,the headgear buckle 570 includes a curved surface 578 that preventscontact of the buckle 570 with the patient's head. The rear straps 599may be coupled to one another by a buckle (as upper straps 598 are) orin any other suitable manner.

The headgear yokes 580 of the headgear assembly 520 include retainingmembers 581 engaged with respective second connector portions 526 so asto retain the second connector portions 526 on the frame 516. In theillustrated embodiment, the retaining members 581 are ring-shaped andenclose the respective second connector portions 526. As shown in FIG.73 , the ring-shaped retaining members 581 have an annular protrusionthat engages within the annular groove 561 in a respective secondconnector portion 526 so as to securely retain the second connectorportions 526 on the frame 516.

Also, the pair of retaining members 581 are engaged with respectivegrooves 561 (FIG. 72 ) provided in second connector portions 526 so asto transfer the headgear force to the frame 516. This allows a moreaccurate adjustment of the force applied by the headgear assembly 520 tothe frame 516. Moreover, the headgear buckle 570 is centrally located onthe patient's head to allow symmetrical adjustment of the headgearassembly 520 and hence adjust the headgear force applied to the frame516.

The angle connectors 542 of the second connector portions 526 arereleasably interlockable with the headgear assembly 520. Specifically,the angle connectors 542 include first locking members 554 (see FIG.74B) that are interlockable with second locking members 556 (see FIG. 80) provided on the headgear yoke 580 of the headgear assembly 520. In theillustrated embodiment, the first locking members 554 are hook-shapedmembers that interlock with a cross-bar provided by the second lockingmembers 556, as shown in FIGS. 81 and 82 . The locking members aretapered and designed to keep a low profile.

FIGS. 84 and 85 illustrate the nasal assembly 510 engaged with nasalpassages of a wearer's nose. As shown in FIG. 84 , the nasal assembly510 is structured such that the angle connectors are angled about 10°below the horizontal so that the nasal assembly 510 avoids contact withthe patient's cheekbone. Also, FIG. 84 shows that the clip 530 whichholds the split ends of the nozzle assembly is angled upwardly andoutwardly away from the lips of the patient, to prevent inadvertentcontact with the patient. The angle may be in the range of 10-90degrees, and preferably 20-60 degrees or about 30 degrees. As shown inFIG. 85 , the second connector portions 526 are angled about 55° fromthe frame 516. The corrugation 538 (FIG. 73 ) may be provided to flex(inward and outward) so as to accommodate patients with faces varying inwidth. However, the angles noted above are only exemplary and the nasalassembly 510 may be structured to provide any suitable angle with thepatient's face.

Similar to the nasal assemblies described above, the inflation of thegusset or base portion 548 along with the headgear tension provides aneffective sealing force against the nasal passages of the patient. Also,the springiness of the nozzles 550 provides an additional sealing force.

Sixth Illustrated Embodiment

FIGS. 86-88 show another embodiment of a nasal assembly 10 structured todeliver breathable gas to the nasal passages 12 of the patient's nose 14(see FIGS. 97A and 97B). The nasal assembly 10 includes a flexibleconduit 16, a gusset portion 18, a pair of nozzles 20, 22, and aheadgear connector 25. The flexible conduit 16 has a portion adapted toreceive a supply of pressurized breathable gas and a patient side 24.The gusset portion 18 has a first side 26 (see FIG. 89 ) attached to thepatient side 24 of the flexible conduit 16 and a second side 28. Thepair of nozzles 20, 22 each have a first portion 30 attached to thesecond side 28 of the gusset portion 18 and a second portion 32structured to sealingly engage with nasal passages 12 of the patient'snose 14 in use and provide a seal between the nasal assembly 10 and thepatient's nasal passages 12 (see FIG. 90 ). The headgear connector 25attaches the flexible conduit 16 to a headgear assembly positioned onthe patient's head. The gusset portion 18 is structured such that it canexpand and contract to alter a distance between the conduit 16 and thepair of nozzles 20, 22, as will be further discussed below.

Alternatively, the gusset portion can be eliminated in favor of a morerigid construction that does not allow significant, if any, expansion orcontraction. Instead, as described above in relation to the other mainillustrated embodiments, the nozzles may be structured to engage thatpatient's nares with some degree of pretension (before the mask is inuse, e.g., pressurized), which pretension can be achieved by compressingthe nozzles in an axial or longitudinal sense.

In the illustrated embodiment, the flexible conduit 16 includes acentral conduit 34, a pair of inlet conduits 36, 38 connected to thecentral conduit 34 by respective inlet connectors 40, 42, and a Y-shapedinlet connector 44 that interconnects the inlet conduits 36, 38. TheY-shaped inlet connector 44 is structured to be connected to a conduitthat is connected to a pressurized supply. The pressurized supplysupplies pressurized breathable gas through the inlet conduits 36, 38and central conduit 34, into the gusset portion 18, and into the nozzles20, 22 for breathing by the patient.

As shown in FIG. 89 , the central conduit 34 includes an upper portion46 and a lower portion 48 that are coupled to one another. Each of theupper and lower portions 46, 48 includes an arcuate transversecross-section such that the upper and lower portions 46, 48 form aconduit when coupled together at respective edges. In the illustratedembodiment, the upper and lower portions 46, 48 are rigidly coupled toone another by an adhesive, such as glue, for example. However, theupper and lower portions 46, 48 may be rigidly coupled to one another byany other suitable means, such as fasteners. Alternatively, the upperand lower portions 46, 48 may be removably coupled to one another, orthey may be formed in a single unitary piece.

As shown in FIGS. 86, 88, 90 and 92-95 , the upper and lower portions46, 48 have a generally C-shape when viewed from above. Specifically,each of the upper and lower portions 46, 48 includes an elongatedcentral section 50 and curved end sections 52, 54. However, the upperand lower portions 46, 48 may have any other suitable shape, such as anelongated shape, as shown in FIG. 89 .

The curved end sections 52, 54 each include a groove 56, as shown inFIG. 94 for example. When the upper and lower portions 46, 48 arecoupled to one another, the grooves 56 retain respective inletconnectors 40, 42, as will be further discussed. At least one of theupper and lower portions 46, 48 includes an anti-crush rib 58 thatprevents the central conduit 34 from deformation that can prevent theflow of air therethrough. In FIG. 89 , the groove 56 is provided onopposing ends thereof.

As shown in FIG. 89 , the upper portion 46 of the central conduit 34includes an opening 60. The gusset portion 18, which is in the form ofan expandable and contractible pillow, includes a first side or sidewall26 and a second side or sidewall 28 that define a space therebetween.The first sidewall 26 is attached to the upper portion 46. The firstsidewall 26 includes an inlet opening that is communicated with theopening 60 in the upper portion 46. The second sidewall 28 has a pair ofoutlet openings. The connection between the gusset portion 18 and theupper portion 46 of the central conduit 34 is a flexible connection thatallows relative movement between the gusset portion 18 and the centralconduit 34, for increased comfort and accommodation of variations inpatient facial features.

In the illustrated embodiment, the gusset portion 18 has a generallyrectangular shape. However, the gusset portion 18 may have a generallycircular or round cross-section, or any other suitable shape, includingshapes to avoid sensitive regions of the patient's face, e.g. notchedgusset shape to prevent contact with the patient's septum.

The pair of nozzles 20, 22 each has a first portion 30 attached thesecond sidewall 28 of the gusset portion 18 in communication with arespective outlet opening of the gusset portion 18. The second portion32 of each of the nozzles 20, 22 is structured to sealingly engage withnasal passages 12 of the patient's nose 14 in use and provide a sealbetween the nasal assembly 10 and the patient's nasal passages 12. Inthe illustrated embodiment, the nozzles 20, 22 are in the form of nasalpillows wherein the second portion 32 is contoured (e.g., tapered,cone-shaped, truncated hollow cone, etc.) with a portion that seals onthe underside of the nostrils and another portion that enters into thenasal passage of the patient's nose in use. However, the nozzles 20, 22may be in the form of nasal prongs, cannula, or nasal puffs, forexample, and may sealingly engage with the nasal passages in anysuitable manner. For example, the nozzles 20, 22 may seal within thenasal passages, against the nasal passages, around the nasal passages,or combinations thereof. The nozzles 20, 22 may include a corrugated orflexible portion that allows the nozzles 20, 22 to move relative to thegusset portion 18 and the central conduit 34. The nozzles 20, 22 may becontoured to match the interior profile of the patient's nose 14.

In one embodiment, the nasal assembly uses patient-customized nozzleswhich may be removably mounted to the gusset portion. In a preferredform, the nozzles are constructed from a substantially flexible polymermaterial, such as a silicone elastomer. A unique nozzle can be made tomatch each patient's nose by first scanning their nose, either in situor remotely, and then using the data for manufacture of the interface,for example, a mold maker. Scanning can be done using either non-contactor contact methods. Non-contact, for example photographically, or byphysical contact with a probe or by collecting an impression of theinside of the nares or the desired contact interface. Once a pair ofsuitable nozzles are made, they are sent to the customer to be fitted toa patient. Advantages of the preformed or customized shape is thatcross-sectional area may be maximized to reduce flow impedance.

Also, the use of preformed shapes improves comfort and increasedstiffness materials such as semi-rigid plastics may be used that havegreater resistance to distorting, thus minimizing nozzle distortion ofthe patient nares. Further, rigid plastics may be used that allows thinwall sections and allows flexibility of the nozzle due to its connectionto the gusset portion, e.g., the gusset portion is soft and compliant.

In the illustrated embodiment, the upper portion 46 of the centralconduit 34 is molded in one piece with the gusset portion 18 and nozzlesor nasal pillows 20, 22 from deformable and inflatable materials. Thecentral conduit 34, nasal pillows 20, 22, and gusset portion 18 may beconstructed from a soft, flexible skin-compatible material such assilicone. The central conduit 34, nasal pillows 20, 22, and gussetportion 18 may be formed, for example, in an injection molding processas is known in the art.

However, the central conduit 34, nasal pillows 20, 22, and gussetportion 18 may be formed with any suitable material and may be formed byany suitable process. For example, the central conduit 34, gussetportion 18, and nasal pillows 20, 22 may be formed separately andpermanently attached to one another with an adhesive, welding, and/ormechanical fasteners, for example. Alternatively, the central conduit34, gusset portion 18, and nasal pillows 20, 22 may be formed separatelyand removably attached to one another.

The lower portion 48 of the central conduit 34 includes an exhaust vent62 and a pair of tapered or barbed protrusions 64 structured to retainthe headgear connector 25 to the central conduit 34. The exhaust vent 62is aligned with the opening 60 in the upper portion 46. The exhaust vent62 protrudes slightly outwardly from the central conduit 34 and includesa series of openings 66 for CO₂ washout.

As shown in FIG. 89 , the headgear connector 25 is in the form of anelongated strap that includes a pair of openings 68 adapted to receiverespective protrusions 64 of the lower portion 48 therethrough and acentral opening 70 adapted to receive the exhaust vent 62 therethrough.Specifically, the openings 68 press over the tapered or barbedprotrusions 64 to retain and locate the headgear connector 25 to thecentral conduit 34.

Further, the headgear connector 25 includes connection structures 72 onfree ends thereof for connection to a headgear assembly (not shown). Theheadgear assembly can be removably connected to the connectionstructures 72 to maintain the nasal assembly 10 in a desired position onthe patient's face. For example, the headgear assembly may includestraps removably connected to respective connection structures 72.

As shown in FIG. 91 , the connection structures 72 may have roundededges. Moreover, the openings 68, 70 may have any suitable shape (e.g.oval, circular, rectangular, etc.). For example, FIG. 91 illustratesopenings 68, 70 with a generally oval shape and FIG. 89 illustratesopenings 68 with a generally circular shape and opening 70 with agenerally rectangular shape.

The headgear connector 25 is constructed of a deformable and resilientmaterial so that it can deform in at least one bending plane, e.g.,around the face of the patient in use. For example, the headgearconnector 25 may be constructed of polypropylene or any other suitablepolymer. Also, the headgear connector 25 may be constructed of a naturalor synthetic fabric material, or a combination of materials such as alaminate combination. The headgear connector 25 is deformable such thatit can conform to the contour of the patient's face when the nasalassembly 10 is mounted to the patient's head. Further, the headgearconnector 25 bears the tension applied by the headgear assembly whichprevents any tension from pulling on, and subsequently distorting, theflexible central conduit 16.

However, the headgear connector 25 may have any suitable structure forconnection to a headgear assembly. For example, the headgear connector25 may be the protrusions 64 provided on the central conduit 34 and theheadgear assembly may attach directly to the protrusions 64.Alternatively, the headgear connector may be in the form of a lockingclip receiver assembly structured to connect to a respective lockingclip provided on the headgear assembly. Details of a locking clipreceiver assembly and locking clips are provided in U.S. ProvisionalApplication of Moore et al., Ser. Nos. 60/377,254, 60/397,195, and60/402,509, all of which are hereby incorporated into the presentapplication by reference in their entireties.

The central conduit 34 is connected to the pair of inlet conduits 36, 38by inlet connectors 40, 42. As shown in FIG. 97 , each inlet connector40, 42 includes a first conduit portion 74 that branches into a pair ofsecond conduit portions 76. The first conduit portion 74 includes aradially expanded flange 78 that is received within a respective groove56 provided by the central conduit 34 on opposing end sections 52, 54thereof. Thus, a first inlet connector 40 is retained to one end section52 of the central conduit 34 and a second inlet connector 42 is retainedto the opposite end section 54 of the central conduit 34.

The inlet conduits 36, 38 each may have a first end connected torespective inlet connectors 40, 42 and a second end connected to theY-shaped inlet connector 44. As shown in FIG. 96 , each of the inletconduits 36, 38 include first and second passageways 80, 82. The pair ofsecond conduit portions 76 of the inlet connector 40, 42 are insertedthrough the first and second passageways 80, 82 of the first end of theinlet conduit 36, 38 to couple the inlet connectors 40, 42 withrespective first ends of the inlet conduits 36, 38. The inlet connectors40, 42 and inlet conduits 36, 38 may retained with a friction-type fit,mechanical fasteners, adhesive, co-molded, insert-molded, or any othersuitable means.

As shown in FIG. 96A, the Y-shaped connector 44 includes a firstconnector 84 that is connected with the second end of one of the inletconduits 36, a second connector 86 that is connected with the second endof other of the inlet conduits 38, and a third connector 88 that isconnected to a pressurized supply for delivering pressurized gas to thenasal assembly 10. Each of the first and second connectors 84, 86includes a pair of conduit portions 90 that are inserted through thefirst and second passageways 80, 82 of the inlet conduit 36, 38 tocouple the Y-shaped connector 44 with respective inlet conduits 36, 38.The third connector 88 may include a swivel mechanism to allow relativemovement between the Y-shaped connector 44 and the delivery conduitconnected to the pressurized supply. The Y-shaped connector 44 and inletconduits 36, 38 may retained with a friction-type fit, mechanicalfasteners, adhesive, welding, insert molding or any other suitablemeans.

As shown in FIG. 98 , the central conduit 34 and inlet conduits 36, 38may be formed of crush-resistant, anti-crush, or anti-kinking tubingsuch as that disclosed in U.S. Pat. No. 6,044,844, the entirety of whichis incorporated herein by reference.

Pressurized gas enters through connector 88 of the Y-shaped connector 44and proceeds through the first and second inlet conduits 36, 38 intoboth end sections of the central conduit 34. Air passes though thecentral conduit 34, into the gusset portion 18 and nasal pillows 20, 22,and into the nasal passages 12 of the patient. Exhaust gases from thepatient's nose can exit through the exhaust vent 62 provided in thecentral conduit 34.

As best shown in FIGS. 86 and 89 , the gusset portion 18 extendsoutwardly from the central conduit 34 to provide additional surface areaor footprint area. As air under pressure enters the central conduit 34,both the central conduit 34 and gusset portion 18 inflate, which movesthe nasal pillows 20, 22 into sealing engagement with the nasal passages12 of the patient. However, the central conduit 34 may not be inflatablealong with the gusset portion 18. That is, the gusset portion 18 isstructured such that it can expand and contract to alter a distancebetween the central conduit 34 and the nasal pillows 20, 22. The gussetportion 18 moves the nasal pillows 20, 22 between a first position (asshown in FIG. 97A) in which the nasal pillows 20, 22 are adjacent to thenasal passages 12 of the patient and a second position (as shown in FIG.97B) in which the nasal pillows 20, 22 are moved into sealing engagementwith the nasal passages 12 of the patient. Specifically, the gussetportion 18 is uninflated or generally flat when not pressurized by agas. However, the gusset portion 18 may not have a generally flatstructure when uninflated. In the uninflated condition, the nasalpillows 20, 22 are spaced from the nasal passages 12 of the patient orin light contact therewith. When the nasal assembly 10 is pressurized bya gas, the gusset portion 18 is inflated and moves the nasal pillows 20,22 into sealing engagement with the nasal passages 12 of the patient toform a seal between the nasal assembly 10 and the patient's nasalpassages 12. As the gas pressure is increased, the force applied to theunderside of the nasal passages 12 is increased through the gussetportion 18.

The gusset portion 18 provides additional surface area or footprint areato the central conduit 34, which in turn provides an additional force onthe nasal pillows 20, 22 which increases the sealing efficiency of thenasal pillows 20, 22. That is, the gusset portion 18 is configured andpositioned to force the nasal pillows 20, 22 into contact with thepatient's nose. The force or pressure on the patient's nose isproportional to the pressure in the central conduit 34 and theadditional surface area of the gusset portion 18. Thus, the surface areaof the gusset portion 18 may be varied, e.g., to vary the force orpressure applied to the patient's nose.

The gusset portion 18 reduces the headgear assembly tension required toachieve a suitable seal. That is, the pressure applied to the patient'snose is provided by the gusset portion 18 and not relied on by thetension from the headgear assembly. This improves patient comfort aswell as sealing properties.

Accordingly, it is desirable when adjusting the headgear assembly tobring the nasal pillows 20, 22 only near or in very light contact withthe patient's nose. In this way, the gusset portion 18 is not compressedsubstantially.

The gusset portion 18 may include a connecting wall between the sidewalls 26, 28 thereof. The connecting wall may act as a spring structureto provide a component of force on the patient's face through the nasalpillows 20, 22. The force may be tailored by adjusting a thickness ofthe connecting wall. Moreover, the thickness of the connecting wall maybe varied in conjunction with the surface area provided by the gussetportion 18.

The gusset portion 18 also provides a decoupling joint between thecentral conduit 34 and the nasal pillows 20, 22, thus allowing somerelative movement between the nasal assembly 10 and the user's face. Asa result, the nasal pillows 20, 22 can accommodate small variations inthe shape of the patient's nasal features without undue force, and canaccount for small movement of the nasal assembly 10 relative to thepatient's nose during use, while maintaining an effective seal.

Also, the gusset portion 18 need not be a single gusset form discussedabove, but can have alternative configurations. For example, the gussetportion 18 may be in the form of a two or more gusset portions providedin series.

FIGS. 98-106 illustrate another embodiment of a nasal assembly,indicated as 210. As best shown in FIGS. 98-100 , the nasal assembly 210includes a central conduit 234, a pair of inlet conduits 236, 238connected to the central conduit 234 (e.g., by an adhesive), and aninlet connector 244 that interconnects the inlet conduits 236, 238. Theinlet connector 244 is structured to be connected to a conduit that isconnected to a pressurized supply. The inlet connector 244 may beaxially swivelable to maximize stability by reducing kinking of theconduits.

A gusset portion 218 is provided that includes first and second sidewalls 226, 228 that define a space therebetween. The first side wall 226includes an inlet opening that is communicated with an opening in thecentral conduit 234. The second side wall 228 has a pair of outletopenings. In the illustrated embodiment, the gusset portion 218 has ageneral bow-tie shape. However, the gusset portion 218 may have anyother suitable shape.

A pair of nozzles 220, 222 in the form of nasal pillows are provided.Each nasal pillow 220, 222 has a first portion 230 attached the secondside wall 228 of the gusset portion 218 in communication with arespective outlet opening of the gusset portion 218. The second portion232 of each of the nasal pillows 220, 222 is structured to sealinglyengage with the nasal passages 12 of the patient's nose 14 in use andprovide a seal between the nasal assembly 210 and the patient's nasalpassages 12.

In the illustrated embodiment, the central conduit 234, inlet conduits236, 238, gusset portion 218, and nasal pillows 220, 222 are constructedfrom flexible materials, such as silicone, and attached to one anotherwith an adhesive. However, the central conduit 234, inlet conduits 236,238, gusset portion 218, and nasal pillows 220, 222 may be molded in onepiece, or formed with any other suitable material in any suitableprocess.

The central conduit 234 includes exhaust vents 262 (FIGS. 100 and 101 )that protrude slightly outwardly therefrom for CO₂ washout. Also, aheadgear connector 225 in the form of a pair of clips 272, are attachedto the conduits 234, 236, 238 (e.g., by an adhesive) for connection to aheadgear assembly 206. The headgear assembly 206 includes straps 207removably connected to respective clips 272 by a hook and loop fastener,for example. As shown in FIGS. 101 and 102 , the straps 207 pass overthe ears of the patient and engage a head cloth 208 that sits on theupper portion of the patient's head to cup the occipital portion of thepatient's head. However, the headgear assembly 206 may have any suitablestructure for maintaining the nasal assembly 210 on the patient's head.

FIGS. 103-106 illustrate the nasal assembly 210 engaged with outer edgesof the nasal passages 12 of the patient's nose 14. Similar to the nasalassembly 10 described above, as air enters the central conduit 234, boththe central conduit 234 and gusset portion 218 inflate, which moves thenasal pillows 220, 222 into sealing engagement with the nasal passages12 of the patient. However, the central conduit 234 may not beinflatable along with the gusset portion 218. That is, the gussetportion 218 moves the nasal pillows 220, 222 between a first position inwhich the nasal pillows 220, 222 are adjacent to the nasal passages 12of the patient and a second position in which the nasal pillows 220, 222are moved into sealing engagement with the nasal passages 12 of thepatient.

In the embodiments of nasal assemblies 10, 210, the inlet conduits 36,38, 236, 238 extend downwardly from the nasal pillows 20, 22, 220, 222away from the patient's head. However, as shown in FIG. 107 , the nasalassembly, indicated as 310, may be an over-the-head type assembly inwhich the inlet conduit(s) 336 extends upwardly from the nasal pillows320, 322 over the head of the patient.

FIG. 107-1 illustrates an embodiment like that shown in FIG. 107 , butwhich includes an adjustable forehead support 411. The forehead support411 includes a first portion 413 provided to a tube support 415.Connection between the first portion 413 and the tube support 415 allowsadjustment of a second portion 417 of the forehead support 411 relativeto the patient's forehead, to achieve the best possible fit. The secondportion 417 includes a bridge 419 to support one or more foreheadcushions or pads 421, as described in U.S. Pat. No. 6,119,693 or in U.S.patent application Ser. No. 10/655,595 (each incorporated herein byreference in its entirety) and headgear connector portions 423 forreleasable connector to headgear straps 425. The headgear connectorportions may take the form of those shown in U.S. Pat. No. 6,374,826,incorporated herein by reference in its entirety, or in U.S. Provisionalapplication No. 60/467,570, incorporated herein by reference in itsentirety. The bridge 419 may include a central portion 427 structured toaccommodate, guide and/or hold an upper portion of air delivery tube asit is guided over the head of the patient. Adjustment may be achievedvia bending, flexing and/or pivoting of the first portion 413 relativeto the support 415. For example, support 415 may include a pivot pin 429which is introduced into an aperture on the first portion 413. Support415 and first portion 413 may include a plurality of locking members 431(e.g., protrusions and recesses), to allow locking of the foreheadsupport 411 in a number (e.g., 3-5, preferably 4) of predeterminedpositions.

FIG. 107-2 illustrates another embodiment of an adjustable foreheadsupport that operates like that disclosed in U.S. Pat. No. 6,532,961,incorporated herein by reference in its entirety.

FIGS. 107A-107C illustrate yet another alternative embodiment of thepresent invention. FIG. 107A is a perspective view of a mask assembly650, while FIG. 107B is a side view of the mask assembly shown in FIG.107A. The mask assembly 650 includes a headgear assembly 652 and a nasalcushion assembly 654. The headgear assembly includes a coronal strap 654and an occipital strap 656.

A flexible tube 658 includes a first end 660 which may include a swivelconnector. The tube 658 is provided with a suitable source ofpressurized gas. The tube includes a second end 662 which is provided tothe cushion assembly 654. The tube 658 is supported by a support frame664. The support frame includes a lower portion 666 which supports acushion 668 of the cushion assembly 654. The support frame also includesa central portion 670 and an upper portion 672. The upper portion 672may include flexible arms separated by a gap. The arms may beresiliently deformed to allow insertion and removal of the tube betweenthe two arms. The support frame 664 may include lateral support arms 674which are configured to rest against the patient's forehead in use. Eachlateral support arm 674 includes first and second connector slots 676and 678 which provide a connection point for coronal strap 654 andoccipital strap 656, respectively.

FIG. 107B is a side view of the mask assembly. FIG. 107C is an enlargedside view of a portion of the assembly 650 shown in FIGS. 107A and 107B.The lower portion 666 of the support frame 664 is adapted to support thecushion 668 as shown therein. The cushion 668 includes a pair of nozzles680 (one shown) which are formed in an integral piece with a plenumchamber 682.

FIGS. 107D and 107E illustrate yet another embodiment of the presentinvention. A mask assembly 690 includes a headgear assembly 692 whichincludes an occipital strap 694, a coronal strap 696 and depending armstraps 698 each of which extends from a junction between the occipitaland coronal straps 694 and 696 and forwardly of the ear along the user'sface. The top portion of the coronal strap 696 may include a suitableconnector 700 such as the flexible arms shown in FIG. 107A.Alternatively, the connector 700 may take the form of a VELCRO® loopwhich helps to fasten a tube 702. The tube 702 includes a first end 704which may be provided with a swivel connector which in turn is connectedto a suitable source of pressurized gas via an air delivery tube. Thetube 702 is routed over the top of the forehead and is generally alignedwith but spaced from the nose and bridge of the patient. A support frame708 includes an upper portion 710 which helps to maintain the tube 702in the desired position. The upper portion 710 may include flexiblearms, like the upper portion 672 in FIG. 107A.

The support 708 may include a pair of lateral arms 714, best illustratedin the side view of FIG. 107E. Each lateral support arm 714 includes aconnector slot 715 which is adapted to receive an end of the dependingarm strap 698.

FIG. 107F illustrates an alternative embodiment of a mask assembly 720including a headgear assembly 722 having the configuration generallycorresponding to that of the letter “X”, including a first cross strap724 and a second cross strap 726. The first and second cross strap 724and 726 meet at a junction or intersection 728. The forward end ofsecond cross strap 726 is provided with a connector element 730, whichmay take the form of a VELCRO® loop. The connector element 730 may beadapted to support and/or hold a transitional tubing piece whichincludes a first end for connecting with relatively large bore tubing732 and a second end for accommodating relatively small bore tubing 734.A support frame 736 is provided to support the tube 734 and a cushion738 in the position shown in FIG. 107F.

FIG. 107G illustrates a mask assembly 750 according to yet anotherembodiment of the present invention. The mask assembly 750 includes aheadgear assembly 752 including a rear strap 754 and a forehead strap756. A depending arm strap 758 extends from a junction between the rearstrap 754 and the forehead strap 756. One or more of the straps mayinclude a yoke member 759 which helps to reinforce and maintain theposition of the straps relative to one another. As shown in FIG. 107G,the mask assembly 750 includes a tube 760 including a first end 762 thatmay include a swivel connector, which can be connected to an airdelivery tube 764, which is in turn provided to a source of pressurizedair.

As shown in FIG. 107H, each strap 758 includes a first connector portion766 having one or more arms 767 which can be resiliently flexed towardone another to insert and remove the connector portion 766 from asuitable recess in frame 768. The frame 768 is provided with a connectorportion 770 which receives and/or connects to the tube 760. As shown inFIG. 107H, only a portion of one of the nozzles 772 is visible.

FIG. 107I illustrates another embodiment of the present invention. Amask assembly 780 includes a headgear assembly 782 including a rearstrap 784 and a forward strap 786. A tube 788 is connected to a junctionconnector 790 which in turn is connected to one or more soft flexibletubes 792 that follow and/or are connected to rear strap 784 on eachside of the user's head. The headgear assembly 782 may include dependingarm straps 783 that are positioned forward of the ear and along thecheek of the user. Each tube 792 may be suitably attached to thedepending arm strap 783. Each tube 792 is suitably connected to acushion assembly 794.

FIG. 107J illustrates still another embodiment of the present invention.A mask assembly 800 may include a headgear assembly, only a portion ofwhich is shown in the drawing. The headgear assembly may includedepending arm straps 802 which support lateral support arms 804 whichare connected or provided to a cushion assembly 812. Each depending armstrap 802 may also support an interchange 806, which may take the formof a U-shape coupling member having a first end connected to an airdelivery tube 808 and a second end connected to tube 810 which isconnected to the cushion assembly 812.

FIGS. 107K and 107L illustrate yet another embodiment of the presentinvention. As shown in FIG. 107K, a cushion assembly includes a frame820, a plenum or bellows chamber 824 and a pair of nozzles 826 mountedon the plenum chamber 824. The cushion assembly may be supported by oneor more lateral support arms 822, as shown in FIG. 107K. Alternatively,the cushion assembly can be supported by a support frame as shown, forexample, in FIG. 107A. As shown in FIG. 107K, the nozzle 826 has arelatively low profile because it is engaged with a patient's nares.However, as shown in FIG. 107L, the nozzle 826 may extend from the lowprofile position shown in FIG. 107K to the higher profile position shownin FIG. 107L, by virtue of its resiliency.

FIGS. 107M-107Q illustrate cross-sections of various nozzles 832, 834,836, 840 and 844 according to the present invention. As shown in FIG.1070 , the nozzle may include a ledge 838 which is intended to rest onthe nostril edge while the middle portion 839 is received by the nare.As shown in FIG. 107P, the nozzle 840 includes a cut away 842 which maybe advantageous to avoid or reduce the chances of rubbing on the centerof the nose. As seen in FIG. 107Q, the nozzle 844 may include aprotrusion 846 to deflect air away from nostril walls. FIG. 107R showsthe position of the protrusions 846 on the nozzles in perspective view.

Seventh Illustrated Embodiment

FIGS. 108-113 illustrate yet another preferred embodiment of the presentinvention. As shown in FIG. 108 , a mask assembly 600 includes headgear602 and a cushion assembly 604, each of which is substantially similarto the headgear and cushion assembly shown, e.g., in FIGS. 60 and 61 ,respectively. Headgear 602 is designed to capture the crown of thepatient's head. Adjustment of strap tension can be accomplished bypulling loose tabs on the top of the head in opposite directions. Thepulling direction is not aligned with the force the nozzle assemblyapplies to the patient. Therefore, the patient is more isolated from thestrap adjustment forces. Yokes provide stability to the sides. Yokesretain at least a partial portion of the basic shape of headgear, whichfacilitates donning of the headgear. Headgear need not includeadjustability toward front of the face, as all adjustment of headgearcan be effected at the back or top of the head.

In the embodiment of FIG. 108 , one end of the cushion assembly 604 isprovided with a plug 622 and the other end is provided with a swivelelbow 612. The positions of the swivel elbow 612 and the plug 622 may beinterchanged, according to preference, e.g., the typical sleepingposition of the patient. An air delivery tube 606 is joined to theswivel elbow 612. The air delivery tube 606 may include a swivelconnector 607 and includes an end 609 which also may be provided with aswivel connector. The end 609 is provided with a source of pressurizedgas.

As shown in FIG. 108 , the elbow 612 is angled about 120′ from thecushion assembly 604. This helps to keep the tube out of line of sight,to minimize pressure drop and to maintain the flexion point of tube asclose to the face as possible. However, the elbow may have a typical 90°bend as shown, e.g., in FIGS. 109 and 110 .

FIG. 109 is a schematic perspective view of the mask assembly 600 shownin FIG. 108 , but only yokes 608 of headgear 602 are shown withoutstraps. As with the fifth main illustrated embodiment, the yoke 608 mayinclude a yoke ring 610. As shown in FIG. 109 , the cushion assembly maybe adjustably rotated with respect to headgear, to a position which bestfits the patient. In FIG. 109 , the ring 610 of the yoke 608 of theheadgear includes an alignment marker 611 a and the cushion includes aplurality of alignment markers 611 b that can be selectively alignedwith marker 611 a.

FIG. 110 is a cross-sectional view of a portion of the cushion assembly604. In particular, the cushion assembly 604 includes a frame 616 whichsupports a cushion 617. The frame 616 includes a first connector portion618 provided to each end of the frame 616 and/or cushion 617. Each firstconnector portion 618 is provided with or to a seal ring 614. Both sealring and plug are examples of second connector portions that areconnected or otherwise provided to the first connector portions 618. Asseen in FIG. 110 , the left hand side of the mask assembly includes theplug 622 while the right hand side of the mask assembly includes theswivel elbow 612, i.e., the reverse arrangement view shown in FIGS. 108and 109 .

FIG. 110 shows that the cushion 617 includes a plurality of ventapertures 619, each of which is designed to reduce noise. Cross-sectionsof two possible aperture profiles are shown in FIGS. 110-1 and 110-2 .In FIG. 110-2 , the end 617 a displaces any potential noise creatingflash (i.e., a molding seam) out of main air path through bore of vent.Stated differently, the molding seam is moved from a position from whereit could potentially create noise, to a position where it is less likelyto create noise.

FIG. 110A is a partial cross-sectional view showing the interactionbetween the seal ring 614, first connector portion 618 and the plug 622.In particular, the seal ring 614 may be provided with first and secondprotrusions 624, 626, respectively. The first protrusion 624 mayinteract with a groove 618 a provided in the first connector portion618, for sealing and/or locking purposes. The second protrusion 626 mayinteract with a groove 628 provided in the plug 622, the sealing and/orlocking purposes. As shown in FIG. 110A, each seal ring 614 includes agroove 630 to receive a respective one of the rings 610 of the yoke 608.In FIG. 110A, the yoke 608 is not shown.

FIG. 110B is an enlarged partial cross-sectional view of the maskassembly 600 on the right hand side of FIG. 110 . A first end 612 a ofthe swivel elbow 612 is inserted in and received within the firstconnector portion 618. The first end 612 a may include an enlarged headportion which prevents inadvertent dislodgment of the swivel elbow 612from the assembly. The front end 612 a may include at least one slot 613to allow the enlarged head portion to reduce its diameter upon insertionby resiliently flexing. Preferably, there are a plurality of such slots,e.g., four slots. The seal ring 614 may include first and secondprotrusions 624, 626, as described above. In this case, the secondprotrusion 626 may interact by friction with the outer circumference ofthe swivel elbow 612, and provide a seal. Moreover, the swivel elbow 612may be provided with a groove or other structure to receive the secondprotrusion 626.

FIG. 110B also schematically shows that the swivel elbow 612 and theseal ring 614 may include a swivel stop 631. For example, the swivelstop 631 may be formed as part of the yoke 608.

Alternatively or in addition, as shown in FIG. 111 , the swivel elbow612 may be provided with a ring 633 including a protrusion 634. The sealring 614 may be modified to include swivel stops 632. Accordingly, theprotrusion 634 may rotate along with swivel elbow 612 until theprotrusion 634 abuts against the swivel stop 632. Therefore, movement ofthe air delivery tube 606 can be confined with a predetermined range ofmovement, e.g., about 220°-300°, and preferably 250°-270°, thusminimizing or avoiding undesirable contact between the air delivery tubeand the patient.

FIG. 112 is a partial cross-sectional view of the assembly of the frame,first connector portion 618, yoke 608, seal ring 614 and plug 622. FIG.112 shows the plug 622 to be inserted in the right hand side of thecushion assembly 604, as shown in FIG. 108 .

FIG. 113 shows an alternative embodiment of the invention in which theplug and seal ring are formed of a single integral piece. As shown inFIG. 113 , the seal ring 636 includes a flange portion 638 whichgenerally follows along a contour of the yoke 608. This is best shown inthe cross-sectional view of FIG. 110 where the seal ring 614 and theyoke 608 are positioned closely adjacent one another.

The seventh main illustrated embodiment may provide for improveddecoupling of the air delivery tube 606 and/or swivel elbow 612 from thecushion assembly 604. In addition, this embodiment provides a choice oftube routing, which can be either up or down or on the left or righthand sides of the cushion assembly 604. As such, this embodiment may beperceived as less obtrusive and is significantly lighter. It alsoincludes less parts than previous embodiments and can be easier tomanufacture, assemble and clean.

The swivel elbow 612 may be provided with a quick release mechanism (notshown). The swivel elbow 612, as shown in FIG. 110B, is able to fit andsnap into the mask frame 616. This construction allows free swivelingwithin the frame 616, between a range of defined angles, therebyensuring that the tube does not get into an uncomfortable position withrespect to the head and pillow.

The seal ring 614 is structured such that it cooperates with thegeometry of the elbow swivel 612. In addition, the seal ring 614 may beconnected to the ring 610 of the yoke 608. The seal ring 614 may bepermanently connected to the ring 610, e.g., via co-molding. Forexample, the swivel stop 631 in FIG. 110B may be formed as part of thering 610. The first connector portion 618 on each side of the frame 616may be rotated with respect to the seal ring 614, to thereby positionthe cushion assembly 604 accordingly. The seal ring 614 seals the swivelelbow 612 preferably with minimum friction. Each seal ring 614 mayaccommodate either the plug 622 or the swivel elbow 612. The seal ring614 is large enough for patients to handle, especially patients withreduced manual dexterity.

The plug 622 may be press fit into the seal ring 614. The plug 622 canalso be designed to be press fit into the frame. The plug 622 may bemade from hard polymer, for example, polypropylene. A recess (not shown)may be provided to remove the plug 622. The plug functions to seal theframe and cushion assembly on the side opposing the air delivery tube.The plug 622 is large enough for patients to handle, even with reducedmanual dexterity.

The tubing 606 may be permanently attached to the end of the swivelelbow 612. However, a push-on friction connection may also be suitable.The tube length may be between 200 mm and 400 mm, preferably 250 and 350mm, for example, or any other length which will not interfere with thepatient's face.

As shown in FIGS. 110B and 111 , respectively, the yokes 608 and sealring 614 may be provided with structure to limit the angular orrotational movement of the swivel elbow 612 with respect to the firstconnector portion 618. Further, the headgear and/or yoke may be providedwith a tube retention feature to control the tube position. For example,simple VELCRO® straps may be provided along some portion of the headgearto restrain movement of the air delivery tube.

In another example shown in FIGS. 108A and 108B, a tube retainer 900includes a first portion 902 to be connected or attached to one of thestraps of headgear. For example, the first portion 902 can be in theform of a loop that is attached to a portion 904 of headgear strap shownin FIG. 108 . Attachment can be accomplished by threading the headgearstrap 904 though the first portion 902 before the headgear strap 904 isthreaded through the headgear buckle 906. The retainer 900 includes asecond portion 908 provided or attached to the first portion 902. Thesecond portion 908 may be made of a resilient plastic that retains theshape shown in FIG. 108A, with a gap 910 defined between two ends 912 ofthe second portion 908. The gap 910 is sized to be smaller than thediameter of the air delivery tube 606, so as to reliably hold the tube606. Alternatively, the second portion 908 can be a VELCRO® loop, withthe ends 912 including the mating hooks and loops. As shown in FIGS.108A and 108B, the second portion may include one or more slots 914 toreceive ribs 916 (FIG. 108 ) of the air delivery tube 606, to therebyprevent axial sliding of the tube 606. With this arrangement, the tube606 can be reliably held in a position over the patient's head.

FIG. 108C illustrates a plan view of a tube retainer, wherein likereference numbers relate to like parts. In FIG. 108C, exemplarydimensions of the tube retainer are shown. It is to be noted that thesedimensions are examples only, and the dimensions can be changed up toabout ±20% of the values shown therein.

The nasal assemblies 10, 210, 310, 410, 510, 600 described above andbelow have several advantages. For example, the nasal assemblies 10,210, 310, 410, 510 are unobtrusive due to their small overall size andweight. The nasal assemblies 10, 210, 310, 410, 510, 600 provide a highlevel of comfort due to the minimal force applied to the patient'snose—and contact with the bridge can be eliminated. The nasal assemblies10, 210, 310, 410, 510, 600 are easy to use and include minimal partsand adjustments, e.g., the inlet conduits can be easily adjusted toextend upwardly over the head of the patient or downwardly below thechin of the patient. The pressurized supply can be easily connected toand disconnected from the connectors without altering the headgearsetting. Also, the nasal assemblies 10, 210, 310, 410, 510, 600 allowfor greater nozzle range of motion to accommodate a wide range ofpatients. That is, the nozzles can be rotated with respect to thepatient's face by rotating the frame relative to the headgear assembly.Further, strap tension need not be as high as the area of contact withthe face is less. The headgear provides stability, e.g., the yokes helpmaintain the mask assembly's position on the face. The adjustment of theheadgear is designed such that the force required to tighten the strapsis not applied to the patient's face, e.g., the straps can be pulled inopposite directions above the head to counteract one another. It isrelatively easy to find balance between performance and comfort. Inaddition, the weight, noise level, and/or number of parts of the maskassembly is reduced.

An Appendix including additional drawings and depictions of variousaspects of preferred embodiments of the invention is included in U.S.Provisional Application No. 60/529,696, filed Dec. 16, 2003 andincorporated herein by reference in its entirety. To the extent that anydrawing in the labeled Figures or the Appendix includes dimensions,those dimensions are exemplary only and may be changed without departingfrom the scope of the disclosure.

FIG. 114 illustrates an exploded view of another embodiment of thepresent invention. In this embodiment, the cushion assembly 604 issimilar to that shown in FIGS. 108-109 , and swivel elbow 612 is asdescribed in relation to FIGS. 108, 110B and 111 . Yoke 608 includes awidened portion 608 a intended to engage with a corresponding widenedportion 630 a adjacent or formed as part of groove 630. In addition,yoke 608 includes a recess 608 b intended to receive ear 638 of sealring 614. In a further embodiment, yoke and seal ring may be formed inone piece. Also, the yoke and headgear could be formed of one piece,instead of using stitching. As can be seen in FIG. 115 , the yoke 608and seal ring 614 can be snap fit relative to one another, e.g., viashoulder 621. By this structure, the yoke and ring are prevented fromrotating relative to one another. FIG. 115 also shows the generalposition of yoke flex point P, which allows a good fit with the patient.

FIGS. 116 to 126 illustrate further views of the embodiment shown inFIGS. 114 and 115 . Another aspect of the arrangement is that the ring610 of the yoke 608 is angularly offset with respect to the main body609 of the yoke 608. Compare FIG. 116 with FIG. 110 , e.g., where themain body 609 in FIG. 116 is twisted. For example, front side 609 a inFIG. 116 is positioned laterally outward in comparison to rear side 609b in FIG. 116 . This structure helps to bias the bottom portion of theyoke 608 towards the patient's face, so that the yoke more closelyfollows the contours of the patient's face.

FIGS. 127-130 illustrate a further embodiment of the present invention.This embodiment is similar to that shown and described in FIGS. 114-126. However, there are two main differences. First, the elbow 612 is freeto rotate 360° within seal ring 614. As shown in the partial explodedview of FIG. 128 , seal ring 614 does not include stops 632 and elbow612 does not include protrusion 634, as compared to what is shown inFIG. 114 .

Second, as shown in FIG. 129 , seal ring 614 includes a selectivelyremovable and insertable cap 614 a. In other words, the plug 622 in FIG.119 is made in two parts rather than one. The cap 614 a may also includea vent, instead of or supplemental to the vent provided on the cushion.FIG. 130 shows a partial exploded view of cap 614 a. Because seal rings614 on both sides of nozzle assembly are identical, the cap 614 a andelbow 612 can be removed and swapped, if the patient opts to have theelbow 612 routed over the left or right side. This can be done while themask assembly is in use on the patient. Also, the elbow 612 can beremoved to allow for patient mobility.

FIGS. 131-133 illustrate an elbow 612 according to yet anotherembodiment. As compared to elbow 612 shown in FIG. 114 , elbow 612 inFIGS. 131-133 includes one and preferably a pair of key-shaped apertures613. The elbow may be made of polypropylene, e.g., “Borealis,” orpolyester. The shape of the apertures allows for improved retention andremoval forces, when the elbow is in place and when it is removed.

Further, the nozzle assembly and/or its associated cushion could bereplaced with a nasal mask and/or nasal cushion. See, e.g., FIGS. 134and 135 . FIG. 134 shows an arrangement in which the frame includesopposite apertures or first connector portions (e.g., tubularextensions), each of which is provided with a seal ring as describedabove. A seal ring 500 is adapted to include a separate or integral plugto close one aperture or first connector portion of the frame, whileanother seal ring is adapted to engage with the other frameaperture/first connector portion, and to receive the swivel elbow. Ofcourse, the positions of the elbow and plug may be interchanged,depending on patient preference. In FIG. 135 , the elbow is provided tothe front of the mask frame, like ReMed's VISTA mask, while bothapertures/first connector portions are provided with plugged seal rings.Of course, in each embodiment, frame, elbow, and/or seal ring(s) may beprovided with appropriate vents to exhaust exhaled gas from thebreathing chamber.

It can thus be appreciated that the aspects of the present inventionhave been fully and effectively accomplished. The foregoing specificembodiments have been provided to illustrate the structural andfunctional principles of the present invention, and are not intended tobe limiting. To the contrary, the present invention is intended toencompass all modifications, alterations, and substitutions within thespirit and scope of the detailed description.

What is claimed is:
 1. A mask assembly to deliver a supply of breathablegas pressurized at positive pressure from a flow generator to the nasalairways of a patient to treat sleep disordered breathing, the maskassembly comprising: a cushion shaped and configured to sealingly engageon an underside of the nose of the patient without contacting the bridgeof the patient's nose in use; a flow generator connector having aconduit connector configured to be connected to a gas supply conduit toreceive the supply of breathable gas from the flow generator, theconduit connector being structured and dimensioned to be positioned ontop of the patient's head in use, the conduit connector having a swivelto allow rotational movement between the flow generator connector andthe gas supply conduit during use; a pair of inlet conduits connected tothe flow generator connector to receive the supply of breathable gas,and in use, each of the pair of inlet conduits configured to bepositioned along a corresponding lateral side of the patient's head,each of the pair of inlet conduits configured to extend from the top ofthe patient's head to proximal to the patient's nose, each of the pairof inlet conduits configured to extend in a superior direction relativeto the cushion between the patient's corresponding eye and ear to createa cushion sealing force with an upwardly oriented component, whereinsuperior ends of the inlet conduits are configured to be positionedclosely adjacent to the top of the patient's head in use; a rear strapconfigured to pass around the rear portion of the patient's head in use;and a pair of intermediate strap connectors, each of the intermediatestrap connectors connected to a corresponding one of inlet conduits,each of the intermediate strap connectors having a hole, and the rearstrap being connected to each of the intermediate strap connectors atthe hole, wherein the mask assembly does not include a center tubeadapted to be routed over the top of the patient's forehead, and whereinthe mask assembly does not have a forehead support.
 2. The mask assemblyof claim 1, further comprising a pair of connector portions, each of thepair of connector portions connected to an inferior end of acorresponding one of the pair of inlet conduits opposite the flowgenerator connector, each of the pair of connector portions beingremovably coupled to the cushion.
 3. The mask assembly of claim 2,wherein the front portion includes a plurality of resiliently flexiblearms that are structured to flex inwardly and outwardly.
 4. The maskassembly of claim 3, wherein a free end of each of the plurality ofresiliently flexible arms includes a rib portion.
 5. The mask assemblyof claim 4, wherein the rib portion is adapted to engage a recess of acushion connector portion to couple each of the pair of inlet conduitsto the cushion.
 6. The mask assembly of claim 1, wherein each of thepair of inlet conduits provides only a single air flow channel.
 7. Themask assembly of claim 1, wherein the pair of inlet conduits areconstructed from silicone.
 8. The mask assembly of claim 1, wherein therear strap is adjustable and is constructed from a flexible compositematerial.
 9. The mask assembly of claim 8, wherein the flexiblecomposite material includes a fabric material and a polymeric material.10. The mask assembly of claim 1, further comprising a pair of connectorportions, each of the pair of connector portions connected to aninferior end of a corresponding one of the pair of inlet conduitsopposite the flow generator connector, each of the pair of connectorportions being removably coupled to the cushion, wherein each of thepair of inlet conduits provides only a single air flow channel, whereinthe pair of inlet conduits are constructed from silicone, wherein thecushion comprises a nasal cushion or a pair of pillows, and wherein therear strap is adjustable and is constructed from a flexible compositematerial.
 11. The mask assembly of claim 1, wherein each of theintermediate strap connectors is curved to avoid contact with thepatient's corresponding ear in use.
 12. The mask assembly of claim 1,wherein each of the intermediate strap connectors is configured to beconnected to a corresponding one of the inlet conduits at a positionthat is superior to the patient's corresponding ear in use.
 13. The maskassembly of claim 1, wherein the hole is positioned on each of theintermediate strap connectors such that in use the rear strap isconnected to each of the intermediate strap connectors posterior to thepatient's anterior auricle line.
 14. A mask assembly to deliver a supplyof breathable gas pressurized at positive pressure from a flow generatorto a patient's airways to treat sleep disordered breathing, the maskassembly comprising: a cushion; a flow generator connector having aconduit connector configured to be connected to a gas supply conduit toreceive the supply of breathable gas from the flow generator, theconduit connector being configured to be held closely adjacent the topof the patient's head in use, the conduit connector being swivelable toallow relative movement between the flow generator connector and the gassupply conduit during use; a pair of inlet conduits connected to theflow generator connector to receive the supply of breathable gas, and inuse, each of the pair of inlet conduits configured to be positionedalong a corresponding lateral side of the patient's head, each of thepair of inlet conduits configured to extend from superior the patient'shead to proximal to the patient's nose, and each of the pair of inletconduits being configured to extend in a superior direction relative tothe cushion between the patient's corresponding eye and ear; a pair ofconnector portions, each of the pair of connector portions connected toan end of a corresponding one of the pair of inlet conduits opposite theflow generator connector, each of the pair of connector portionsconfigured to be removably coupled to the cushion; an adjustable rearstrap connecting each of the pair of inlet conduits, and configured topass around the rear portion of the patient's head in use; and a pair ofintermediate strap connectors, each of the intermediate strap connectorsconnected to a corresponding one of inlet conduits, each of theintermediate strap connectors having a hole, and the adjustable rearstrap being connected to each of the intermediate strap connectors atthe hole.
 15. The mask assembly of claim 14, wherein each of the pair ofconnector portions includes a main body having a front portion and arear portion.
 16. The mask assembly of claim 15, wherein the frontportion includes a plurality of resiliently flexible arms that arestructured to flex inwardly and outwardly.
 17. The mask assembly ofclaim 16, wherein a free end of each of the plurality of resilientlyflexible arms includes a rib portion.
 18. The mask assembly of claim 17,wherein the cushion includes a pair of cushion connector portions, eachof the pair of cushion connector portions having a recess, and whereinthe rib portion is adapted to engage a corresponding recess to coupleeach of the pair of inlet conduits to the cushion.
 19. The mask assemblyof claim 14, wherein each of the pair of inlet conduits provides only asingle air flow channel.
 20. The mask assembly of claim 14, furthercomprising a series of openings for CO₂ washout.
 21. The mask assemblyof claim 14, wherein the cushion further comprises a gusset portion. 22.The mask assembly of claim 14, wherein the pair of inlet conduits areconstructed from silicone.
 23. The mask assembly of claim 14, whereinthe adjustable rear strap is constructed from a flexible compositematerial.
 24. The mask assembly of claim 23, wherein the flexiblecomposite material includes a fabric material and a polymeric material.25. The mask assembly of claim 14, wherein: the pair of inlet conduitsand the adjustable rear strap are configured to maintain the flowgenerator connector in a position superior to the patient's head in use,each of the pair of connector portions includes a main body having afront portion and a rear portion, the front portion includes a pluralityof resiliently flexible arms that are structured to flex inwardly andoutwardly, a free end of each of the plurality of resiliently flexiblearms includes a rib portion, the cushion includes a pair of cushionconnector portions, each of the pair of cushion connector portionshaving a recess, the rib portion is adapted to engage a correspondingrecess to couple each of the pair of inlet conduits to the cushion, eachof the pair of inlet conduits provides only a single air flow channel,the mask assembly further comprises a series of openings for CO₂washout, the cushion comprises a nasal mask or a pair of pillows; thepair of inlet conduits are constructed from silicone, the mask assemblyincludes means for reducing tube pull forces from being applied to thetubes; and the adjustable rear strap is constructed from a flexiblecomposite material.
 26. The mask assembly of claim 14, wherein each ofthe intermediate strap connectors is curved to avoid contact with thepatient's corresponding ear in use.
 27. The mask assembly of claim 14,wherein each of the intermediate strap connectors is configured to beconnected to a corresponding one of the inlet conduits at a positionthat is superior to the patient's corresponding ear in use.
 28. The maskassembly of claim 14, wherein the hole is positioned on each of theintermediate strap connectors such that in use the adjustable rear strapis connected to each of the intermediate strap connectors posterior tothe patient's anterior auricle line.